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10376 lines
480 KiB
10376 lines
480 KiB
#ifndef USE_LIBSQLITE3 |
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/* |
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** 2001 September 15 |
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** |
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** The author disclaims copyright to this source code. In place of |
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** a legal notice, here is a blessing: |
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** |
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** May you do good and not evil. |
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** May you find forgiveness for yourself and forgive others. |
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** May you share freely, never taking more than you give. |
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** |
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************************************************************************* |
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** This header file defines the interface that the SQLite library |
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** presents to client programs. If a C-function, structure, datatype, |
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** or constant definition does not appear in this file, then it is |
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** not a published API of SQLite, is subject to change without |
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** notice, and should not be referenced by programs that use SQLite. |
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** |
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** Some of the definitions that are in this file are marked as |
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** "experimental". Experimental interfaces are normally new |
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** features recently added to SQLite. We do not anticipate changes |
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** to experimental interfaces but reserve the right to make minor changes |
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** if experience from use "in the wild" suggest such changes are prudent. |
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** |
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** The official C-language API documentation for SQLite is derived |
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** from comments in this file. This file is the authoritative source |
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** on how SQLite interfaces are supposed to operate. |
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** |
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** The name of this file under configuration management is "sqlite.h.in". |
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** The makefile makes some minor changes to this file (such as inserting |
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** the version number) and changes its name to "sqlite3.h" as |
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** part of the build process. |
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*/ |
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#ifndef SQLITE3_H |
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#define SQLITE3_H |
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#include <stdarg.h> /* Needed for the definition of va_list */ |
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|
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/* |
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** Make sure we can call this stuff from C++. |
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*/ |
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#ifdef __cplusplus |
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extern "C" { |
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#endif |
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|
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|
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/* |
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** Provide the ability to override linkage features of the interface. |
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*/ |
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#ifndef SQLITE_EXTERN |
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# define SQLITE_EXTERN extern |
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#endif |
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#ifndef SQLITE_API |
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# define SQLITE_API |
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#endif |
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#ifndef SQLITE_CDECL |
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# define SQLITE_CDECL |
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#endif |
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#ifndef SQLITE_APICALL |
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# define SQLITE_APICALL |
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#endif |
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#ifndef SQLITE_STDCALL |
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# define SQLITE_STDCALL SQLITE_APICALL |
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#endif |
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#ifndef SQLITE_CALLBACK |
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# define SQLITE_CALLBACK |
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#endif |
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#ifndef SQLITE_SYSAPI |
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# define SQLITE_SYSAPI |
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#endif |
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|
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/* |
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** These no-op macros are used in front of interfaces to mark those |
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** interfaces as either deprecated or experimental. New applications |
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** should not use deprecated interfaces - they are supported for backwards |
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** compatibility only. Application writers should be aware that |
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** experimental interfaces are subject to change in point releases. |
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** |
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** These macros used to resolve to various kinds of compiler magic that |
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** would generate warning messages when they were used. But that |
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** compiler magic ended up generating such a flurry of bug reports |
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** that we have taken it all out and gone back to using simple |
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** noop macros. |
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*/ |
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#define SQLITE_DEPRECATED |
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#define SQLITE_EXPERIMENTAL |
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|
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/* |
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** Ensure these symbols were not defined by some previous header file. |
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*/ |
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#ifdef SQLITE_VERSION |
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# undef SQLITE_VERSION |
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#endif |
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#ifdef SQLITE_VERSION_NUMBER |
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# undef SQLITE_VERSION_NUMBER |
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#endif |
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|
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/* |
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** CAPI3REF: Compile-Time Library Version Numbers |
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** |
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** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header |
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** evaluates to a string literal that is the SQLite version in the |
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** format "X.Y.Z" where X is the major version number (always 3 for |
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** SQLite3) and Y is the minor version number and Z is the release number.)^ |
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** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer |
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** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same |
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** numbers used in [SQLITE_VERSION].)^ |
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** The SQLITE_VERSION_NUMBER for any given release of SQLite will also |
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** be larger than the release from which it is derived. Either Y will |
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** be held constant and Z will be incremented or else Y will be incremented |
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** and Z will be reset to zero. |
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** |
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** Since [version 3.6.18] ([dateof:3.6.18]), |
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** SQLite source code has been stored in the |
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** <a href="http://www.fossil-scm.org/">Fossil configuration management |
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** system</a>. ^The SQLITE_SOURCE_ID macro evaluates to |
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** a string which identifies a particular check-in of SQLite |
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** within its configuration management system. ^The SQLITE_SOURCE_ID |
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** string contains the date and time of the check-in (UTC) and an SHA1 |
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** hash of the entire source tree. |
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** |
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** See also: [sqlite3_libversion()], |
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** [sqlite3_libversion_number()], [sqlite3_sourceid()], |
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** [sqlite_version()] and [sqlite_source_id()]. |
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*/ |
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#define SQLITE_VERSION "3.15.1" |
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#define SQLITE_VERSION_NUMBER 3015001 |
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#define SQLITE_SOURCE_ID "2016-11-04 12:08:49 1136863c76576110e710dd5d69ab6bf347c65e36" |
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/* |
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** CAPI3REF: Run-Time Library Version Numbers |
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** KEYWORDS: sqlite3_version, sqlite3_sourceid |
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** |
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** These interfaces provide the same information as the [SQLITE_VERSION], |
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** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros |
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** but are associated with the library instead of the header file. ^(Cautious |
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** programmers might include assert() statements in their application to |
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** verify that values returned by these interfaces match the macros in |
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** the header, and thus ensure that the application is |
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** compiled with matching library and header files. |
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** |
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** <blockquote><pre> |
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** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER ); |
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** assert( strcmp(sqlite3_sourceid(),SQLITE_SOURCE_ID)==0 ); |
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** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 ); |
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** </pre></blockquote>)^ |
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** |
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** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION] |
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** macro. ^The sqlite3_libversion() function returns a pointer to the |
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** to the sqlite3_version[] string constant. The sqlite3_libversion() |
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** function is provided for use in DLLs since DLL users usually do not have |
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** direct access to string constants within the DLL. ^The |
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** sqlite3_libversion_number() function returns an integer equal to |
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** [SQLITE_VERSION_NUMBER]. ^The sqlite3_sourceid() function returns |
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** a pointer to a string constant whose value is the same as the |
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** [SQLITE_SOURCE_ID] C preprocessor macro. |
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** |
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** See also: [sqlite_version()] and [sqlite_source_id()]. |
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*/ |
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SQLITE_API SQLITE_EXTERN const char sqlite3_version[]; |
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SQLITE_API const char *sqlite3_libversion(void); |
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SQLITE_API const char *sqlite3_sourceid(void); |
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SQLITE_API int sqlite3_libversion_number(void); |
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|
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/* |
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** CAPI3REF: Run-Time Library Compilation Options Diagnostics |
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** |
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** ^The sqlite3_compileoption_used() function returns 0 or 1 |
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** indicating whether the specified option was defined at |
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** compile time. ^The SQLITE_ prefix may be omitted from the |
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** option name passed to sqlite3_compileoption_used(). |
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** |
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** ^The sqlite3_compileoption_get() function allows iterating |
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** over the list of options that were defined at compile time by |
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** returning the N-th compile time option string. ^If N is out of range, |
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** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_ |
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** prefix is omitted from any strings returned by |
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** sqlite3_compileoption_get(). |
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** |
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** ^Support for the diagnostic functions sqlite3_compileoption_used() |
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** and sqlite3_compileoption_get() may be omitted by specifying the |
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** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time. |
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** |
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** See also: SQL functions [sqlite_compileoption_used()] and |
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** [sqlite_compileoption_get()] and the [compile_options pragma]. |
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*/ |
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#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS |
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SQLITE_API int sqlite3_compileoption_used(const char *zOptName); |
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SQLITE_API const char *sqlite3_compileoption_get(int N); |
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#endif |
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|
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/* |
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** CAPI3REF: Test To See If The Library Is Threadsafe |
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** |
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** ^The sqlite3_threadsafe() function returns zero if and only if |
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** SQLite was compiled with mutexing code omitted due to the |
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** [SQLITE_THREADSAFE] compile-time option being set to 0. |
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** |
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** SQLite can be compiled with or without mutexes. When |
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** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes |
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** are enabled and SQLite is threadsafe. When the |
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** [SQLITE_THREADSAFE] macro is 0, |
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** the mutexes are omitted. Without the mutexes, it is not safe |
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** to use SQLite concurrently from more than one thread. |
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** |
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** Enabling mutexes incurs a measurable performance penalty. |
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** So if speed is of utmost importance, it makes sense to disable |
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** the mutexes. But for maximum safety, mutexes should be enabled. |
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** ^The default behavior is for mutexes to be enabled. |
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** |
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** This interface can be used by an application to make sure that the |
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** version of SQLite that it is linking against was compiled with |
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** the desired setting of the [SQLITE_THREADSAFE] macro. |
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** |
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** This interface only reports on the compile-time mutex setting |
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** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with |
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** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but |
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** can be fully or partially disabled using a call to [sqlite3_config()] |
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** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD], |
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** or [SQLITE_CONFIG_SERIALIZED]. ^(The return value of the |
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** sqlite3_threadsafe() function shows only the compile-time setting of |
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** thread safety, not any run-time changes to that setting made by |
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** sqlite3_config(). In other words, the return value from sqlite3_threadsafe() |
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** is unchanged by calls to sqlite3_config().)^ |
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** |
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** See the [threading mode] documentation for additional information. |
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*/ |
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SQLITE_API int sqlite3_threadsafe(void); |
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|
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/* |
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** CAPI3REF: Database Connection Handle |
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** KEYWORDS: {database connection} {database connections} |
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** |
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** Each open SQLite database is represented by a pointer to an instance of |
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** the opaque structure named "sqlite3". It is useful to think of an sqlite3 |
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** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and |
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** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()] |
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** and [sqlite3_close_v2()] are its destructors. There are many other |
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** interfaces (such as |
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** [sqlite3_prepare_v2()], [sqlite3_create_function()], and |
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** [sqlite3_busy_timeout()] to name but three) that are methods on an |
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** sqlite3 object. |
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*/ |
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typedef struct sqlite3 sqlite3; |
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|
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/* |
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** CAPI3REF: 64-Bit Integer Types |
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** KEYWORDS: sqlite_int64 sqlite_uint64 |
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** |
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** Because there is no cross-platform way to specify 64-bit integer types |
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** SQLite includes typedefs for 64-bit signed and unsigned integers. |
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** |
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** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions. |
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** The sqlite_int64 and sqlite_uint64 types are supported for backwards |
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** compatibility only. |
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** |
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** ^The sqlite3_int64 and sqlite_int64 types can store integer values |
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** between -9223372036854775808 and +9223372036854775807 inclusive. ^The |
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** sqlite3_uint64 and sqlite_uint64 types can store integer values |
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** between 0 and +18446744073709551615 inclusive. |
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*/ |
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#ifdef SQLITE_INT64_TYPE |
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typedef SQLITE_INT64_TYPE sqlite_int64; |
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typedef unsigned SQLITE_INT64_TYPE sqlite_uint64; |
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#elif defined(_MSC_VER) || defined(__BORLANDC__) |
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typedef __int64 sqlite_int64; |
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typedef unsigned __int64 sqlite_uint64; |
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#else |
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typedef long long int sqlite_int64; |
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typedef unsigned long long int sqlite_uint64; |
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#endif |
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typedef sqlite_int64 sqlite3_int64; |
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typedef sqlite_uint64 sqlite3_uint64; |
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/* |
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** If compiling for a processor that lacks floating point support, |
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** substitute integer for floating-point. |
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*/ |
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#ifdef SQLITE_OMIT_FLOATING_POINT |
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# define double sqlite3_int64 |
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#endif |
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|
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/* |
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** CAPI3REF: Closing A Database Connection |
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** DESTRUCTOR: sqlite3 |
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** |
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** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors |
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** for the [sqlite3] object. |
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** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if |
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** the [sqlite3] object is successfully destroyed and all associated |
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** resources are deallocated. |
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** |
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** ^If the database connection is associated with unfinalized prepared |
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** statements or unfinished sqlite3_backup objects then sqlite3_close() |
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** will leave the database connection open and return [SQLITE_BUSY]. |
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** ^If sqlite3_close_v2() is called with unfinalized prepared statements |
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** and/or unfinished sqlite3_backups, then the database connection becomes |
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** an unusable "zombie" which will automatically be deallocated when the |
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** last prepared statement is finalized or the last sqlite3_backup is |
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** finished. The sqlite3_close_v2() interface is intended for use with |
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** host languages that are garbage collected, and where the order in which |
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** destructors are called is arbitrary. |
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** |
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** Applications should [sqlite3_finalize | finalize] all [prepared statements], |
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** [sqlite3_blob_close | close] all [BLOB handles], and |
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** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated |
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** with the [sqlite3] object prior to attempting to close the object. ^If |
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** sqlite3_close_v2() is called on a [database connection] that still has |
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** outstanding [prepared statements], [BLOB handles], and/or |
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** [sqlite3_backup] objects then it returns [SQLITE_OK] and the deallocation |
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** of resources is deferred until all [prepared statements], [BLOB handles], |
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** and [sqlite3_backup] objects are also destroyed. |
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** |
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** ^If an [sqlite3] object is destroyed while a transaction is open, |
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** the transaction is automatically rolled back. |
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** |
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** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)] |
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** must be either a NULL |
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** pointer or an [sqlite3] object pointer obtained |
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** from [sqlite3_open()], [sqlite3_open16()], or |
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** [sqlite3_open_v2()], and not previously closed. |
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** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer |
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** argument is a harmless no-op. |
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*/ |
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SQLITE_API int sqlite3_close(sqlite3*); |
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SQLITE_API int sqlite3_close_v2(sqlite3*); |
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|
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/* |
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** The type for a callback function. |
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** This is legacy and deprecated. It is included for historical |
|
** compatibility and is not documented. |
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*/ |
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typedef int (*sqlite3_callback)(void*,int,char**, char**); |
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|
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/* |
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** CAPI3REF: One-Step Query Execution Interface |
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** METHOD: sqlite3 |
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** |
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** The sqlite3_exec() interface is a convenience wrapper around |
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** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()], |
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** that allows an application to run multiple statements of SQL |
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** without having to use a lot of C code. |
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** |
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** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded, |
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** semicolon-separate SQL statements passed into its 2nd argument, |
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** in the context of the [database connection] passed in as its 1st |
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** argument. ^If the callback function of the 3rd argument to |
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** sqlite3_exec() is not NULL, then it is invoked for each result row |
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** coming out of the evaluated SQL statements. ^The 4th argument to |
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** sqlite3_exec() is relayed through to the 1st argument of each |
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** callback invocation. ^If the callback pointer to sqlite3_exec() |
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** is NULL, then no callback is ever invoked and result rows are |
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** ignored. |
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** |
|
** ^If an error occurs while evaluating the SQL statements passed into |
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** sqlite3_exec(), then execution of the current statement stops and |
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** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec() |
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** is not NULL then any error message is written into memory obtained |
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** from [sqlite3_malloc()] and passed back through the 5th parameter. |
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** To avoid memory leaks, the application should invoke [sqlite3_free()] |
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** on error message strings returned through the 5th parameter of |
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** sqlite3_exec() after the error message string is no longer needed. |
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** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors |
|
** occur, then sqlite3_exec() sets the pointer in its 5th parameter to |
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** NULL before returning. |
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** |
|
** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec() |
|
** routine returns SQLITE_ABORT without invoking the callback again and |
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** without running any subsequent SQL statements. |
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** |
|
** ^The 2nd argument to the sqlite3_exec() callback function is the |
|
** number of columns in the result. ^The 3rd argument to the sqlite3_exec() |
|
** callback is an array of pointers to strings obtained as if from |
|
** [sqlite3_column_text()], one for each column. ^If an element of a |
|
** result row is NULL then the corresponding string pointer for the |
|
** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the |
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** sqlite3_exec() callback is an array of pointers to strings where each |
|
** entry represents the name of corresponding result column as obtained |
|
** from [sqlite3_column_name()]. |
|
** |
|
** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer |
|
** to an empty string, or a pointer that contains only whitespace and/or |
|
** SQL comments, then no SQL statements are evaluated and the database |
|
** is not changed. |
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** |
|
** Restrictions: |
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** |
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** <ul> |
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** <li> The application must ensure that the 1st parameter to sqlite3_exec() |
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** is a valid and open [database connection]. |
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** <li> The application must not close the [database connection] specified by |
|
** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running. |
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** <li> The application must not modify the SQL statement text passed into |
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** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running. |
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** </ul> |
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*/ |
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SQLITE_API int sqlite3_exec( |
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sqlite3*, /* An open database */ |
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const char *sql, /* SQL to be evaluated */ |
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int (*callback)(void*,int,char**,char**), /* Callback function */ |
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void *, /* 1st argument to callback */ |
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char **errmsg /* Error msg written here */ |
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); |
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|
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/* |
|
** CAPI3REF: Result Codes |
|
** KEYWORDS: {result code definitions} |
|
** |
|
** Many SQLite functions return an integer result code from the set shown |
|
** here in order to indicate success or failure. |
|
** |
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** New error codes may be added in future versions of SQLite. |
|
** |
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** See also: [extended result code definitions] |
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*/ |
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#define SQLITE_OK 0 /* Successful result */ |
|
/* beginning-of-error-codes */ |
|
#define SQLITE_ERROR 1 /* SQL error or missing database */ |
|
#define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */ |
|
#define SQLITE_PERM 3 /* Access permission denied */ |
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#define SQLITE_ABORT 4 /* Callback routine requested an abort */ |
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#define SQLITE_BUSY 5 /* The database file is locked */ |
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#define SQLITE_LOCKED 6 /* A table in the database is locked */ |
|
#define SQLITE_NOMEM 7 /* A malloc() failed */ |
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#define SQLITE_READONLY 8 /* Attempt to write a readonly database */ |
|
#define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/ |
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#define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */ |
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#define SQLITE_CORRUPT 11 /* The database disk image is malformed */ |
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#define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */ |
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#define SQLITE_FULL 13 /* Insertion failed because database is full */ |
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#define SQLITE_CANTOPEN 14 /* Unable to open the database file */ |
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#define SQLITE_PROTOCOL 15 /* Database lock protocol error */ |
|
#define SQLITE_EMPTY 16 /* Database is empty */ |
|
#define SQLITE_SCHEMA 17 /* The database schema changed */ |
|
#define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */ |
|
#define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */ |
|
#define SQLITE_MISMATCH 20 /* Data type mismatch */ |
|
#define SQLITE_MISUSE 21 /* Library used incorrectly */ |
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#define SQLITE_NOLFS 22 /* Uses OS features not supported on host */ |
|
#define SQLITE_AUTH 23 /* Authorization denied */ |
|
#define SQLITE_FORMAT 24 /* Auxiliary database format error */ |
|
#define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */ |
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#define SQLITE_NOTADB 26 /* File opened that is not a database file */ |
|
#define SQLITE_NOTICE 27 /* Notifications from sqlite3_log() */ |
|
#define SQLITE_WARNING 28 /* Warnings from sqlite3_log() */ |
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#define SQLITE_ROW 100 /* sqlite3_step() has another row ready */ |
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#define SQLITE_DONE 101 /* sqlite3_step() has finished executing */ |
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/* end-of-error-codes */ |
|
|
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/* |
|
** CAPI3REF: Extended Result Codes |
|
** KEYWORDS: {extended result code definitions} |
|
** |
|
** In its default configuration, SQLite API routines return one of 30 integer |
|
** [result codes]. However, experience has shown that many of |
|
** these result codes are too coarse-grained. They do not provide as |
|
** much information about problems as programmers might like. In an effort to |
|
** address this, newer versions of SQLite (version 3.3.8 [dateof:3.3.8] |
|
** and later) include |
|
** support for additional result codes that provide more detailed information |
|
** about errors. These [extended result codes] are enabled or disabled |
|
** on a per database connection basis using the |
|
** [sqlite3_extended_result_codes()] API. Or, the extended code for |
|
** the most recent error can be obtained using |
|
** [sqlite3_extended_errcode()]. |
|
*/ |
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#define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8)) |
|
#define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8)) |
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#define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8)) |
|
#define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8)) |
|
#define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8)) |
|
#define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8)) |
|
#define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8)) |
|
#define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8)) |
|
#define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8)) |
|
#define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8)) |
|
#define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8)) |
|
#define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8)) |
|
#define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8)) |
|
#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8)) |
|
#define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8)) |
|
#define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8)) |
|
#define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8)) |
|
#define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8)) |
|
#define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8)) |
|
#define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8)) |
|
#define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8)) |
|
#define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8)) |
|
#define SQLITE_IOERR_DELETE_NOENT (SQLITE_IOERR | (23<<8)) |
|
#define SQLITE_IOERR_MMAP (SQLITE_IOERR | (24<<8)) |
|
#define SQLITE_IOERR_GETTEMPPATH (SQLITE_IOERR | (25<<8)) |
|
#define SQLITE_IOERR_CONVPATH (SQLITE_IOERR | (26<<8)) |
|
#define SQLITE_IOERR_VNODE (SQLITE_IOERR | (27<<8)) |
|
#define SQLITE_IOERR_AUTH (SQLITE_IOERR | (28<<8)) |
|
#define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8)) |
|
#define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8)) |
|
#define SQLITE_BUSY_SNAPSHOT (SQLITE_BUSY | (2<<8)) |
|
#define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8)) |
|
#define SQLITE_CANTOPEN_ISDIR (SQLITE_CANTOPEN | (2<<8)) |
|
#define SQLITE_CANTOPEN_FULLPATH (SQLITE_CANTOPEN | (3<<8)) |
|
#define SQLITE_CANTOPEN_CONVPATH (SQLITE_CANTOPEN | (4<<8)) |
|
#define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8)) |
|
#define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8)) |
|
#define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8)) |
|
#define SQLITE_READONLY_ROLLBACK (SQLITE_READONLY | (3<<8)) |
|
#define SQLITE_READONLY_DBMOVED (SQLITE_READONLY | (4<<8)) |
|
#define SQLITE_ABORT_ROLLBACK (SQLITE_ABORT | (2<<8)) |
|
#define SQLITE_CONSTRAINT_CHECK (SQLITE_CONSTRAINT | (1<<8)) |
|
#define SQLITE_CONSTRAINT_COMMITHOOK (SQLITE_CONSTRAINT | (2<<8)) |
|
#define SQLITE_CONSTRAINT_FOREIGNKEY (SQLITE_CONSTRAINT | (3<<8)) |
|
#define SQLITE_CONSTRAINT_FUNCTION (SQLITE_CONSTRAINT | (4<<8)) |
|
#define SQLITE_CONSTRAINT_NOTNULL (SQLITE_CONSTRAINT | (5<<8)) |
|
#define SQLITE_CONSTRAINT_PRIMARYKEY (SQLITE_CONSTRAINT | (6<<8)) |
|
#define SQLITE_CONSTRAINT_TRIGGER (SQLITE_CONSTRAINT | (7<<8)) |
|
#define SQLITE_CONSTRAINT_UNIQUE (SQLITE_CONSTRAINT | (8<<8)) |
|
#define SQLITE_CONSTRAINT_VTAB (SQLITE_CONSTRAINT | (9<<8)) |
|
#define SQLITE_CONSTRAINT_ROWID (SQLITE_CONSTRAINT |(10<<8)) |
|
#define SQLITE_NOTICE_RECOVER_WAL (SQLITE_NOTICE | (1<<8)) |
|
#define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8)) |
|
#define SQLITE_WARNING_AUTOINDEX (SQLITE_WARNING | (1<<8)) |
|
#define SQLITE_AUTH_USER (SQLITE_AUTH | (1<<8)) |
|
#define SQLITE_OK_LOAD_PERMANENTLY (SQLITE_OK | (1<<8)) |
|
|
|
/* |
|
** CAPI3REF: Flags For File Open Operations |
|
** |
|
** These bit values are intended for use in the |
|
** 3rd parameter to the [sqlite3_open_v2()] interface and |
|
** in the 4th parameter to the [sqlite3_vfs.xOpen] method. |
|
*/ |
|
#define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */ |
|
#define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */ |
|
#define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */ |
|
#define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */ |
|
#define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */ |
|
#define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */ |
|
#define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */ |
|
#define SQLITE_OPEN_MEMORY 0x00000080 /* Ok for sqlite3_open_v2() */ |
|
#define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */ |
|
#define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */ |
|
#define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */ |
|
#define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */ |
|
#define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */ |
|
#define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */ |
|
#define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */ |
|
#define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */ |
|
#define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */ |
|
#define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */ |
|
#define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */ |
|
#define SQLITE_OPEN_WAL 0x00080000 /* VFS only */ |
|
|
|
/* Reserved: 0x00F00000 */ |
|
|
|
/* |
|
** CAPI3REF: Device Characteristics |
|
** |
|
** The xDeviceCharacteristics method of the [sqlite3_io_methods] |
|
** object returns an integer which is a vector of these |
|
** bit values expressing I/O characteristics of the mass storage |
|
** device that holds the file that the [sqlite3_io_methods] |
|
** refers to. |
|
** |
|
** The SQLITE_IOCAP_ATOMIC property means that all writes of |
|
** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values |
|
** mean that writes of blocks that are nnn bytes in size and |
|
** are aligned to an address which is an integer multiple of |
|
** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means |
|
** that when data is appended to a file, the data is appended |
|
** first then the size of the file is extended, never the other |
|
** way around. The SQLITE_IOCAP_SEQUENTIAL property means that |
|
** information is written to disk in the same order as calls |
|
** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that |
|
** after reboot following a crash or power loss, the only bytes in a |
|
** file that were written at the application level might have changed |
|
** and that adjacent bytes, even bytes within the same sector are |
|
** guaranteed to be unchanged. The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN |
|
** flag indicate that a file cannot be deleted when open. The |
|
** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on |
|
** read-only media and cannot be changed even by processes with |
|
** elevated privileges. |
|
*/ |
|
#define SQLITE_IOCAP_ATOMIC 0x00000001 |
|
#define SQLITE_IOCAP_ATOMIC512 0x00000002 |
|
#define SQLITE_IOCAP_ATOMIC1K 0x00000004 |
|
#define SQLITE_IOCAP_ATOMIC2K 0x00000008 |
|
#define SQLITE_IOCAP_ATOMIC4K 0x00000010 |
|
#define SQLITE_IOCAP_ATOMIC8K 0x00000020 |
|
#define SQLITE_IOCAP_ATOMIC16K 0x00000040 |
|
#define SQLITE_IOCAP_ATOMIC32K 0x00000080 |
|
#define SQLITE_IOCAP_ATOMIC64K 0x00000100 |
|
#define SQLITE_IOCAP_SAFE_APPEND 0x00000200 |
|
#define SQLITE_IOCAP_SEQUENTIAL 0x00000400 |
|
#define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800 |
|
#define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000 |
|
#define SQLITE_IOCAP_IMMUTABLE 0x00002000 |
|
|
|
/* |
|
** CAPI3REF: File Locking Levels |
|
** |
|
** SQLite uses one of these integer values as the second |
|
** argument to calls it makes to the xLock() and xUnlock() methods |
|
** of an [sqlite3_io_methods] object. |
|
*/ |
|
#define SQLITE_LOCK_NONE 0 |
|
#define SQLITE_LOCK_SHARED 1 |
|
#define SQLITE_LOCK_RESERVED 2 |
|
#define SQLITE_LOCK_PENDING 3 |
|
#define SQLITE_LOCK_EXCLUSIVE 4 |
|
|
|
/* |
|
** CAPI3REF: Synchronization Type Flags |
|
** |
|
** When SQLite invokes the xSync() method of an |
|
** [sqlite3_io_methods] object it uses a combination of |
|
** these integer values as the second argument. |
|
** |
|
** When the SQLITE_SYNC_DATAONLY flag is used, it means that the |
|
** sync operation only needs to flush data to mass storage. Inode |
|
** information need not be flushed. If the lower four bits of the flag |
|
** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics. |
|
** If the lower four bits equal SQLITE_SYNC_FULL, that means |
|
** to use Mac OS X style fullsync instead of fsync(). |
|
** |
|
** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags |
|
** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL |
|
** settings. The [synchronous pragma] determines when calls to the |
|
** xSync VFS method occur and applies uniformly across all platforms. |
|
** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how |
|
** energetic or rigorous or forceful the sync operations are and |
|
** only make a difference on Mac OSX for the default SQLite code. |
|
** (Third-party VFS implementations might also make the distinction |
|
** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the |
|
** operating systems natively supported by SQLite, only Mac OSX |
|
** cares about the difference.) |
|
*/ |
|
#define SQLITE_SYNC_NORMAL 0x00002 |
|
#define SQLITE_SYNC_FULL 0x00003 |
|
#define SQLITE_SYNC_DATAONLY 0x00010 |
|
|
|
/* |
|
** CAPI3REF: OS Interface Open File Handle |
|
** |
|
** An [sqlite3_file] object represents an open file in the |
|
** [sqlite3_vfs | OS interface layer]. Individual OS interface |
|
** implementations will |
|
** want to subclass this object by appending additional fields |
|
** for their own use. The pMethods entry is a pointer to an |
|
** [sqlite3_io_methods] object that defines methods for performing |
|
** I/O operations on the open file. |
|
*/ |
|
typedef struct sqlite3_file sqlite3_file; |
|
struct sqlite3_file { |
|
const struct sqlite3_io_methods *pMethods; /* Methods for an open file */ |
|
}; |
|
|
|
/* |
|
** CAPI3REF: OS Interface File Virtual Methods Object |
|
** |
|
** Every file opened by the [sqlite3_vfs.xOpen] method populates an |
|
** [sqlite3_file] object (or, more commonly, a subclass of the |
|
** [sqlite3_file] object) with a pointer to an instance of this object. |
|
** This object defines the methods used to perform various operations |
|
** against the open file represented by the [sqlite3_file] object. |
|
** |
|
** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element |
|
** to a non-NULL pointer, then the sqlite3_io_methods.xClose method |
|
** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The |
|
** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen] |
|
** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element |
|
** to NULL. |
|
** |
|
** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or |
|
** [SQLITE_SYNC_FULL]. The first choice is the normal fsync(). |
|
** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY] |
|
** flag may be ORed in to indicate that only the data of the file |
|
** and not its inode needs to be synced. |
|
** |
|
** The integer values to xLock() and xUnlock() are one of |
|
** <ul> |
|
** <li> [SQLITE_LOCK_NONE], |
|
** <li> [SQLITE_LOCK_SHARED], |
|
** <li> [SQLITE_LOCK_RESERVED], |
|
** <li> [SQLITE_LOCK_PENDING], or |
|
** <li> [SQLITE_LOCK_EXCLUSIVE]. |
|
** </ul> |
|
** xLock() increases the lock. xUnlock() decreases the lock. |
|
** The xCheckReservedLock() method checks whether any database connection, |
|
** either in this process or in some other process, is holding a RESERVED, |
|
** PENDING, or EXCLUSIVE lock on the file. It returns true |
|
** if such a lock exists and false otherwise. |
|
** |
|
** The xFileControl() method is a generic interface that allows custom |
|
** VFS implementations to directly control an open file using the |
|
** [sqlite3_file_control()] interface. The second "op" argument is an |
|
** integer opcode. The third argument is a generic pointer intended to |
|
** point to a structure that may contain arguments or space in which to |
|
** write return values. Potential uses for xFileControl() might be |
|
** functions to enable blocking locks with timeouts, to change the |
|
** locking strategy (for example to use dot-file locks), to inquire |
|
** about the status of a lock, or to break stale locks. The SQLite |
|
** core reserves all opcodes less than 100 for its own use. |
|
** A [file control opcodes | list of opcodes] less than 100 is available. |
|
** Applications that define a custom xFileControl method should use opcodes |
|
** greater than 100 to avoid conflicts. VFS implementations should |
|
** return [SQLITE_NOTFOUND] for file control opcodes that they do not |
|
** recognize. |
|
** |
|
** The xSectorSize() method returns the sector size of the |
|
** device that underlies the file. The sector size is the |
|
** minimum write that can be performed without disturbing |
|
** other bytes in the file. The xDeviceCharacteristics() |
|
** method returns a bit vector describing behaviors of the |
|
** underlying device: |
|
** |
|
** <ul> |
|
** <li> [SQLITE_IOCAP_ATOMIC] |
|
** <li> [SQLITE_IOCAP_ATOMIC512] |
|
** <li> [SQLITE_IOCAP_ATOMIC1K] |
|
** <li> [SQLITE_IOCAP_ATOMIC2K] |
|
** <li> [SQLITE_IOCAP_ATOMIC4K] |
|
** <li> [SQLITE_IOCAP_ATOMIC8K] |
|
** <li> [SQLITE_IOCAP_ATOMIC16K] |
|
** <li> [SQLITE_IOCAP_ATOMIC32K] |
|
** <li> [SQLITE_IOCAP_ATOMIC64K] |
|
** <li> [SQLITE_IOCAP_SAFE_APPEND] |
|
** <li> [SQLITE_IOCAP_SEQUENTIAL] |
|
** </ul> |
|
** |
|
** The SQLITE_IOCAP_ATOMIC property means that all writes of |
|
** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values |
|
** mean that writes of blocks that are nnn bytes in size and |
|
** are aligned to an address which is an integer multiple of |
|
** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means |
|
** that when data is appended to a file, the data is appended |
|
** first then the size of the file is extended, never the other |
|
** way around. The SQLITE_IOCAP_SEQUENTIAL property means that |
|
** information is written to disk in the same order as calls |
|
** to xWrite(). |
|
** |
|
** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill |
|
** in the unread portions of the buffer with zeros. A VFS that |
|
** fails to zero-fill short reads might seem to work. However, |
|
** failure to zero-fill short reads will eventually lead to |
|
** database corruption. |
|
*/ |
|
typedef struct sqlite3_io_methods sqlite3_io_methods; |
|
struct sqlite3_io_methods { |
|
int iVersion; |
|
int (*xClose)(sqlite3_file*); |
|
int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst); |
|
int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst); |
|
int (*xTruncate)(sqlite3_file*, sqlite3_int64 size); |
|
int (*xSync)(sqlite3_file*, int flags); |
|
int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize); |
|
int (*xLock)(sqlite3_file*, int); |
|
int (*xUnlock)(sqlite3_file*, int); |
|
int (*xCheckReservedLock)(sqlite3_file*, int *pResOut); |
|
int (*xFileControl)(sqlite3_file*, int op, void *pArg); |
|
int (*xSectorSize)(sqlite3_file*); |
|
int (*xDeviceCharacteristics)(sqlite3_file*); |
|
/* Methods above are valid for version 1 */ |
|
int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**); |
|
int (*xShmLock)(sqlite3_file*, int offset, int n, int flags); |
|
void (*xShmBarrier)(sqlite3_file*); |
|
int (*xShmUnmap)(sqlite3_file*, int deleteFlag); |
|
/* Methods above are valid for version 2 */ |
|
int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp); |
|
int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p); |
|
/* Methods above are valid for version 3 */ |
|
/* Additional methods may be added in future releases */ |
|
}; |
|
|
|
/* |
|
** CAPI3REF: Standard File Control Opcodes |
|
** KEYWORDS: {file control opcodes} {file control opcode} |
|
** |
|
** These integer constants are opcodes for the xFileControl method |
|
** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()] |
|
** interface. |
|
** |
|
** <ul> |
|
** <li>[[SQLITE_FCNTL_LOCKSTATE]] |
|
** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This |
|
** opcode causes the xFileControl method to write the current state of |
|
** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED], |
|
** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE]) |
|
** into an integer that the pArg argument points to. This capability |
|
** is used during testing and is only available when the SQLITE_TEST |
|
** compile-time option is used. |
|
** |
|
** <li>[[SQLITE_FCNTL_SIZE_HINT]] |
|
** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS |
|
** layer a hint of how large the database file will grow to be during the |
|
** current transaction. This hint is not guaranteed to be accurate but it |
|
** is often close. The underlying VFS might choose to preallocate database |
|
** file space based on this hint in order to help writes to the database |
|
** file run faster. |
|
** |
|
** <li>[[SQLITE_FCNTL_CHUNK_SIZE]] |
|
** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS |
|
** extends and truncates the database file in chunks of a size specified |
|
** by the user. The fourth argument to [sqlite3_file_control()] should |
|
** point to an integer (type int) containing the new chunk-size to use |
|
** for the nominated database. Allocating database file space in large |
|
** chunks (say 1MB at a time), may reduce file-system fragmentation and |
|
** improve performance on some systems. |
|
** |
|
** <li>[[SQLITE_FCNTL_FILE_POINTER]] |
|
** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer |
|
** to the [sqlite3_file] object associated with a particular database |
|
** connection. See also [SQLITE_FCNTL_JOURNAL_POINTER]. |
|
** |
|
** <li>[[SQLITE_FCNTL_JOURNAL_POINTER]] |
|
** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer |
|
** to the [sqlite3_file] object associated with the journal file (either |
|
** the [rollback journal] or the [write-ahead log]) for a particular database |
|
** connection. See also [SQLITE_FCNTL_FILE_POINTER]. |
|
** |
|
** <li>[[SQLITE_FCNTL_SYNC_OMITTED]] |
|
** No longer in use. |
|
** |
|
** <li>[[SQLITE_FCNTL_SYNC]] |
|
** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and |
|
** sent to the VFS immediately before the xSync method is invoked on a |
|
** database file descriptor. Or, if the xSync method is not invoked |
|
** because the user has configured SQLite with |
|
** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place |
|
** of the xSync method. In most cases, the pointer argument passed with |
|
** this file-control is NULL. However, if the database file is being synced |
|
** as part of a multi-database commit, the argument points to a nul-terminated |
|
** string containing the transactions master-journal file name. VFSes that |
|
** do not need this signal should silently ignore this opcode. Applications |
|
** should not call [sqlite3_file_control()] with this opcode as doing so may |
|
** disrupt the operation of the specialized VFSes that do require it. |
|
** |
|
** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]] |
|
** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite |
|
** and sent to the VFS after a transaction has been committed immediately |
|
** but before the database is unlocked. VFSes that do not need this signal |
|
** should silently ignore this opcode. Applications should not call |
|
** [sqlite3_file_control()] with this opcode as doing so may disrupt the |
|
** operation of the specialized VFSes that do require it. |
|
** |
|
** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]] |
|
** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic |
|
** retry counts and intervals for certain disk I/O operations for the |
|
** windows [VFS] in order to provide robustness in the presence of |
|
** anti-virus programs. By default, the windows VFS will retry file read, |
|
** file write, and file delete operations up to 10 times, with a delay |
|
** of 25 milliseconds before the first retry and with the delay increasing |
|
** by an additional 25 milliseconds with each subsequent retry. This |
|
** opcode allows these two values (10 retries and 25 milliseconds of delay) |
|
** to be adjusted. The values are changed for all database connections |
|
** within the same process. The argument is a pointer to an array of two |
|
** integers where the first integer i the new retry count and the second |
|
** integer is the delay. If either integer is negative, then the setting |
|
** is not changed but instead the prior value of that setting is written |
|
** into the array entry, allowing the current retry settings to be |
|
** interrogated. The zDbName parameter is ignored. |
|
** |
|
** <li>[[SQLITE_FCNTL_PERSIST_WAL]] |
|
** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the |
|
** persistent [WAL | Write Ahead Log] setting. By default, the auxiliary |
|
** write ahead log and shared memory files used for transaction control |
|
** are automatically deleted when the latest connection to the database |
|
** closes. Setting persistent WAL mode causes those files to persist after |
|
** close. Persisting the files is useful when other processes that do not |
|
** have write permission on the directory containing the database file want |
|
** to read the database file, as the WAL and shared memory files must exist |
|
** in order for the database to be readable. The fourth parameter to |
|
** [sqlite3_file_control()] for this opcode should be a pointer to an integer. |
|
** That integer is 0 to disable persistent WAL mode or 1 to enable persistent |
|
** WAL mode. If the integer is -1, then it is overwritten with the current |
|
** WAL persistence setting. |
|
** |
|
** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]] |
|
** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the |
|
** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting |
|
** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the |
|
** xDeviceCharacteristics methods. The fourth parameter to |
|
** [sqlite3_file_control()] for this opcode should be a pointer to an integer. |
|
** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage |
|
** mode. If the integer is -1, then it is overwritten with the current |
|
** zero-damage mode setting. |
|
** |
|
** <li>[[SQLITE_FCNTL_OVERWRITE]] |
|
** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening |
|
** a write transaction to indicate that, unless it is rolled back for some |
|
** reason, the entire database file will be overwritten by the current |
|
** transaction. This is used by VACUUM operations. |
|
** |
|
** <li>[[SQLITE_FCNTL_VFSNAME]] |
|
** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of |
|
** all [VFSes] in the VFS stack. The names are of all VFS shims and the |
|
** final bottom-level VFS are written into memory obtained from |
|
** [sqlite3_malloc()] and the result is stored in the char* variable |
|
** that the fourth parameter of [sqlite3_file_control()] points to. |
|
** The caller is responsible for freeing the memory when done. As with |
|
** all file-control actions, there is no guarantee that this will actually |
|
** do anything. Callers should initialize the char* variable to a NULL |
|
** pointer in case this file-control is not implemented. This file-control |
|
** is intended for diagnostic use only. |
|
** |
|
** <li>[[SQLITE_FCNTL_VFS_POINTER]] |
|
** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level |
|
** [VFSes] currently in use. ^(The argument X in |
|
** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be |
|
** of type "[sqlite3_vfs] **". This opcodes will set *X |
|
** to a pointer to the top-level VFS.)^ |
|
** ^When there are multiple VFS shims in the stack, this opcode finds the |
|
** upper-most shim only. |
|
** |
|
** <li>[[SQLITE_FCNTL_PRAGMA]] |
|
** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA] |
|
** file control is sent to the open [sqlite3_file] object corresponding |
|
** to the database file to which the pragma statement refers. ^The argument |
|
** to the [SQLITE_FCNTL_PRAGMA] file control is an array of |
|
** pointers to strings (char**) in which the second element of the array |
|
** is the name of the pragma and the third element is the argument to the |
|
** pragma or NULL if the pragma has no argument. ^The handler for an |
|
** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element |
|
** of the char** argument point to a string obtained from [sqlite3_mprintf()] |
|
** or the equivalent and that string will become the result of the pragma or |
|
** the error message if the pragma fails. ^If the |
|
** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal |
|
** [PRAGMA] processing continues. ^If the [SQLITE_FCNTL_PRAGMA] |
|
** file control returns [SQLITE_OK], then the parser assumes that the |
|
** VFS has handled the PRAGMA itself and the parser generates a no-op |
|
** prepared statement if result string is NULL, or that returns a copy |
|
** of the result string if the string is non-NULL. |
|
** ^If the [SQLITE_FCNTL_PRAGMA] file control returns |
|
** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means |
|
** that the VFS encountered an error while handling the [PRAGMA] and the |
|
** compilation of the PRAGMA fails with an error. ^The [SQLITE_FCNTL_PRAGMA] |
|
** file control occurs at the beginning of pragma statement analysis and so |
|
** it is able to override built-in [PRAGMA] statements. |
|
** |
|
** <li>[[SQLITE_FCNTL_BUSYHANDLER]] |
|
** ^The [SQLITE_FCNTL_BUSYHANDLER] |
|
** file-control may be invoked by SQLite on the database file handle |
|
** shortly after it is opened in order to provide a custom VFS with access |
|
** to the connections busy-handler callback. The argument is of type (void **) |
|
** - an array of two (void *) values. The first (void *) actually points |
|
** to a function of type (int (*)(void *)). In order to invoke the connections |
|
** busy-handler, this function should be invoked with the second (void *) in |
|
** the array as the only argument. If it returns non-zero, then the operation |
|
** should be retried. If it returns zero, the custom VFS should abandon the |
|
** current operation. |
|
** |
|
** <li>[[SQLITE_FCNTL_TEMPFILENAME]] |
|
** ^Application can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control |
|
** to have SQLite generate a |
|
** temporary filename using the same algorithm that is followed to generate |
|
** temporary filenames for TEMP tables and other internal uses. The |
|
** argument should be a char** which will be filled with the filename |
|
** written into memory obtained from [sqlite3_malloc()]. The caller should |
|
** invoke [sqlite3_free()] on the result to avoid a memory leak. |
|
** |
|
** <li>[[SQLITE_FCNTL_MMAP_SIZE]] |
|
** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the |
|
** maximum number of bytes that will be used for memory-mapped I/O. |
|
** The argument is a pointer to a value of type sqlite3_int64 that |
|
** is an advisory maximum number of bytes in the file to memory map. The |
|
** pointer is overwritten with the old value. The limit is not changed if |
|
** the value originally pointed to is negative, and so the current limit |
|
** can be queried by passing in a pointer to a negative number. This |
|
** file-control is used internally to implement [PRAGMA mmap_size]. |
|
** |
|
** <li>[[SQLITE_FCNTL_TRACE]] |
|
** The [SQLITE_FCNTL_TRACE] file control provides advisory information |
|
** to the VFS about what the higher layers of the SQLite stack are doing. |
|
** This file control is used by some VFS activity tracing [shims]. |
|
** The argument is a zero-terminated string. Higher layers in the |
|
** SQLite stack may generate instances of this file control if |
|
** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled. |
|
** |
|
** <li>[[SQLITE_FCNTL_HAS_MOVED]] |
|
** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a |
|
** pointer to an integer and it writes a boolean into that integer depending |
|
** on whether or not the file has been renamed, moved, or deleted since it |
|
** was first opened. |
|
** |
|
** <li>[[SQLITE_FCNTL_WIN32_GET_HANDLE]] |
|
** The [SQLITE_FCNTL_WIN32_GET_HANDLE] opcode can be used to obtain the |
|
** underlying native file handle associated with a file handle. This file |
|
** control interprets its argument as a pointer to a native file handle and |
|
** writes the resulting value there. |
|
** |
|
** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]] |
|
** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging. This |
|
** opcode causes the xFileControl method to swap the file handle with the one |
|
** pointed to by the pArg argument. This capability is used during testing |
|
** and only needs to be supported when SQLITE_TEST is defined. |
|
** |
|
** <li>[[SQLITE_FCNTL_WAL_BLOCK]] |
|
** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might |
|
** be advantageous to block on the next WAL lock if the lock is not immediately |
|
** available. The WAL subsystem issues this signal during rare |
|
** circumstances in order to fix a problem with priority inversion. |
|
** Applications should <em>not</em> use this file-control. |
|
** |
|
** <li>[[SQLITE_FCNTL_ZIPVFS]] |
|
** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other |
|
** VFS should return SQLITE_NOTFOUND for this opcode. |
|
** |
|
** <li>[[SQLITE_FCNTL_RBU]] |
|
** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by |
|
** the RBU extension only. All other VFS should return SQLITE_NOTFOUND for |
|
** this opcode. |
|
** </ul> |
|
*/ |
|
#define SQLITE_FCNTL_LOCKSTATE 1 |
|
#define SQLITE_FCNTL_GET_LOCKPROXYFILE 2 |
|
#define SQLITE_FCNTL_SET_LOCKPROXYFILE 3 |
|
#define SQLITE_FCNTL_LAST_ERRNO 4 |
|
#define SQLITE_FCNTL_SIZE_HINT 5 |
|
#define SQLITE_FCNTL_CHUNK_SIZE 6 |
|
#define SQLITE_FCNTL_FILE_POINTER 7 |
|
#define SQLITE_FCNTL_SYNC_OMITTED 8 |
|
#define SQLITE_FCNTL_WIN32_AV_RETRY 9 |
|
#define SQLITE_FCNTL_PERSIST_WAL 10 |
|
#define SQLITE_FCNTL_OVERWRITE 11 |
|
#define SQLITE_FCNTL_VFSNAME 12 |
|
#define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13 |
|
#define SQLITE_FCNTL_PRAGMA 14 |
|
#define SQLITE_FCNTL_BUSYHANDLER 15 |
|
#define SQLITE_FCNTL_TEMPFILENAME 16 |
|
#define SQLITE_FCNTL_MMAP_SIZE 18 |
|
#define SQLITE_FCNTL_TRACE 19 |
|
#define SQLITE_FCNTL_HAS_MOVED 20 |
|
#define SQLITE_FCNTL_SYNC 21 |
|
#define SQLITE_FCNTL_COMMIT_PHASETWO 22 |
|
#define SQLITE_FCNTL_WIN32_SET_HANDLE 23 |
|
#define SQLITE_FCNTL_WAL_BLOCK 24 |
|
#define SQLITE_FCNTL_ZIPVFS 25 |
|
#define SQLITE_FCNTL_RBU 26 |
|
#define SQLITE_FCNTL_VFS_POINTER 27 |
|
#define SQLITE_FCNTL_JOURNAL_POINTER 28 |
|
#define SQLITE_FCNTL_WIN32_GET_HANDLE 29 |
|
|
|
/* deprecated names */ |
|
#define SQLITE_GET_LOCKPROXYFILE SQLITE_FCNTL_GET_LOCKPROXYFILE |
|
#define SQLITE_SET_LOCKPROXYFILE SQLITE_FCNTL_SET_LOCKPROXYFILE |
|
#define SQLITE_LAST_ERRNO SQLITE_FCNTL_LAST_ERRNO |
|
|
|
|
|
/* |
|
** CAPI3REF: Mutex Handle |
|
** |
|
** The mutex module within SQLite defines [sqlite3_mutex] to be an |
|
** abstract type for a mutex object. The SQLite core never looks |
|
** at the internal representation of an [sqlite3_mutex]. It only |
|
** deals with pointers to the [sqlite3_mutex] object. |
|
** |
|
** Mutexes are created using [sqlite3_mutex_alloc()]. |
|
*/ |
|
typedef struct sqlite3_mutex sqlite3_mutex; |
|
|
|
/* |
|
** CAPI3REF: Loadable Extension Thunk |
|
** |
|
** A pointer to the opaque sqlite3_api_routines structure is passed as |
|
** the third parameter to entry points of [loadable extensions]. This |
|
** structure must be typedefed in order to work around compiler warnings |
|
** on some platforms. |
|
*/ |
|
typedef struct sqlite3_api_routines sqlite3_api_routines; |
|
|
|
/* |
|
** CAPI3REF: OS Interface Object |
|
** |
|
** An instance of the sqlite3_vfs object defines the interface between |
|
** the SQLite core and the underlying operating system. The "vfs" |
|
** in the name of the object stands for "virtual file system". See |
|
** the [VFS | VFS documentation] for further information. |
|
** |
|
** The value of the iVersion field is initially 1 but may be larger in |
|
** future versions of SQLite. Additional fields may be appended to this |
|
** object when the iVersion value is increased. Note that the structure |
|
** of the sqlite3_vfs object changes in the transaction between |
|
** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not |
|
** modified. |
|
** |
|
** The szOsFile field is the size of the subclassed [sqlite3_file] |
|
** structure used by this VFS. mxPathname is the maximum length of |
|
** a pathname in this VFS. |
|
** |
|
** Registered sqlite3_vfs objects are kept on a linked list formed by |
|
** the pNext pointer. The [sqlite3_vfs_register()] |
|
** and [sqlite3_vfs_unregister()] interfaces manage this list |
|
** in a thread-safe way. The [sqlite3_vfs_find()] interface |
|
** searches the list. Neither the application code nor the VFS |
|
** implementation should use the pNext pointer. |
|
** |
|
** The pNext field is the only field in the sqlite3_vfs |
|
** structure that SQLite will ever modify. SQLite will only access |
|
** or modify this field while holding a particular static mutex. |
|
** The application should never modify anything within the sqlite3_vfs |
|
** object once the object has been registered. |
|
** |
|
** The zName field holds the name of the VFS module. The name must |
|
** be unique across all VFS modules. |
|
** |
|
** [[sqlite3_vfs.xOpen]] |
|
** ^SQLite guarantees that the zFilename parameter to xOpen |
|
** is either a NULL pointer or string obtained |
|
** from xFullPathname() with an optional suffix added. |
|
** ^If a suffix is added to the zFilename parameter, it will |
|
** consist of a single "-" character followed by no more than |
|
** 11 alphanumeric and/or "-" characters. |
|
** ^SQLite further guarantees that |
|
** the string will be valid and unchanged until xClose() is |
|
** called. Because of the previous sentence, |
|
** the [sqlite3_file] can safely store a pointer to the |
|
** filename if it needs to remember the filename for some reason. |
|
** If the zFilename parameter to xOpen is a NULL pointer then xOpen |
|
** must invent its own temporary name for the file. ^Whenever the |
|
** xFilename parameter is NULL it will also be the case that the |
|
** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE]. |
|
** |
|
** The flags argument to xOpen() includes all bits set in |
|
** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()] |
|
** or [sqlite3_open16()] is used, then flags includes at least |
|
** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. |
|
** If xOpen() opens a file read-only then it sets *pOutFlags to |
|
** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set. |
|
** |
|
** ^(SQLite will also add one of the following flags to the xOpen() |
|
** call, depending on the object being opened: |
|
** |
|
** <ul> |
|
** <li> [SQLITE_OPEN_MAIN_DB] |
|
** <li> [SQLITE_OPEN_MAIN_JOURNAL] |
|
** <li> [SQLITE_OPEN_TEMP_DB] |
|
** <li> [SQLITE_OPEN_TEMP_JOURNAL] |
|
** <li> [SQLITE_OPEN_TRANSIENT_DB] |
|
** <li> [SQLITE_OPEN_SUBJOURNAL] |
|
** <li> [SQLITE_OPEN_MASTER_JOURNAL] |
|
** <li> [SQLITE_OPEN_WAL] |
|
** </ul>)^ |
|
** |
|
** The file I/O implementation can use the object type flags to |
|
** change the way it deals with files. For example, an application |
|
** that does not care about crash recovery or rollback might make |
|
** the open of a journal file a no-op. Writes to this journal would |
|
** also be no-ops, and any attempt to read the journal would return |
|
** SQLITE_IOERR. Or the implementation might recognize that a database |
|
** file will be doing page-aligned sector reads and writes in a random |
|
** order and set up its I/O subsystem accordingly. |
|
** |
|
** SQLite might also add one of the following flags to the xOpen method: |
|
** |
|
** <ul> |
|
** <li> [SQLITE_OPEN_DELETEONCLOSE] |
|
** <li> [SQLITE_OPEN_EXCLUSIVE] |
|
** </ul> |
|
** |
|
** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be |
|
** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE] |
|
** will be set for TEMP databases and their journals, transient |
|
** databases, and subjournals. |
|
** |
|
** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction |
|
** with the [SQLITE_OPEN_CREATE] flag, which are both directly |
|
** analogous to the O_EXCL and O_CREAT flags of the POSIX open() |
|
** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the |
|
** SQLITE_OPEN_CREATE, is used to indicate that file should always |
|
** be created, and that it is an error if it already exists. |
|
** It is <i>not</i> used to indicate the file should be opened |
|
** for exclusive access. |
|
** |
|
** ^At least szOsFile bytes of memory are allocated by SQLite |
|
** to hold the [sqlite3_file] structure passed as the third |
|
** argument to xOpen. The xOpen method does not have to |
|
** allocate the structure; it should just fill it in. Note that |
|
** the xOpen method must set the sqlite3_file.pMethods to either |
|
** a valid [sqlite3_io_methods] object or to NULL. xOpen must do |
|
** this even if the open fails. SQLite expects that the sqlite3_file.pMethods |
|
** element will be valid after xOpen returns regardless of the success |
|
** or failure of the xOpen call. |
|
** |
|
** [[sqlite3_vfs.xAccess]] |
|
** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS] |
|
** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to |
|
** test whether a file is readable and writable, or [SQLITE_ACCESS_READ] |
|
** to test whether a file is at least readable. The file can be a |
|
** directory. |
|
** |
|
** ^SQLite will always allocate at least mxPathname+1 bytes for the |
|
** output buffer xFullPathname. The exact size of the output buffer |
|
** is also passed as a parameter to both methods. If the output buffer |
|
** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is |
|
** handled as a fatal error by SQLite, vfs implementations should endeavor |
|
** to prevent this by setting mxPathname to a sufficiently large value. |
|
** |
|
** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64() |
|
** interfaces are not strictly a part of the filesystem, but they are |
|
** included in the VFS structure for completeness. |
|
** The xRandomness() function attempts to return nBytes bytes |
|
** of good-quality randomness into zOut. The return value is |
|
** the actual number of bytes of randomness obtained. |
|
** The xSleep() method causes the calling thread to sleep for at |
|
** least the number of microseconds given. ^The xCurrentTime() |
|
** method returns a Julian Day Number for the current date and time as |
|
** a floating point value. |
|
** ^The xCurrentTimeInt64() method returns, as an integer, the Julian |
|
** Day Number multiplied by 86400000 (the number of milliseconds in |
|
** a 24-hour day). |
|
** ^SQLite will use the xCurrentTimeInt64() method to get the current |
|
** date and time if that method is available (if iVersion is 2 or |
|
** greater and the function pointer is not NULL) and will fall back |
|
** to xCurrentTime() if xCurrentTimeInt64() is unavailable. |
|
** |
|
** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces |
|
** are not used by the SQLite core. These optional interfaces are provided |
|
** by some VFSes to facilitate testing of the VFS code. By overriding |
|
** system calls with functions under its control, a test program can |
|
** simulate faults and error conditions that would otherwise be difficult |
|
** or impossible to induce. The set of system calls that can be overridden |
|
** varies from one VFS to another, and from one version of the same VFS to the |
|
** next. Applications that use these interfaces must be prepared for any |
|
** or all of these interfaces to be NULL or for their behavior to change |
|
** from one release to the next. Applications must not attempt to access |
|
** any of these methods if the iVersion of the VFS is less than 3. |
|
*/ |
|
typedef struct sqlite3_vfs sqlite3_vfs; |
|
typedef void (*sqlite3_syscall_ptr)(void); |
|
struct sqlite3_vfs { |
|
int iVersion; /* Structure version number (currently 3) */ |
|
int szOsFile; /* Size of subclassed sqlite3_file */ |
|
int mxPathname; /* Maximum file pathname length */ |
|
sqlite3_vfs *pNext; /* Next registered VFS */ |
|
const char *zName; /* Name of this virtual file system */ |
|
void *pAppData; /* Pointer to application-specific data */ |
|
int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*, |
|
int flags, int *pOutFlags); |
|
int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir); |
|
int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut); |
|
int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut); |
|
void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename); |
|
void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg); |
|
void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void); |
|
void (*xDlClose)(sqlite3_vfs*, void*); |
|
int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut); |
|
int (*xSleep)(sqlite3_vfs*, int microseconds); |
|
int (*xCurrentTime)(sqlite3_vfs*, double*); |
|
int (*xGetLastError)(sqlite3_vfs*, int, char *); |
|
/* |
|
** The methods above are in version 1 of the sqlite_vfs object |
|
** definition. Those that follow are added in version 2 or later |
|
*/ |
|
int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*); |
|
/* |
|
** The methods above are in versions 1 and 2 of the sqlite_vfs object. |
|
** Those below are for version 3 and greater. |
|
*/ |
|
int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr); |
|
sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName); |
|
const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName); |
|
/* |
|
** The methods above are in versions 1 through 3 of the sqlite_vfs object. |
|
** New fields may be appended in future versions. The iVersion |
|
** value will increment whenever this happens. |
|
*/ |
|
}; |
|
|
|
/* |
|
** CAPI3REF: Flags for the xAccess VFS method |
|
** |
|
** These integer constants can be used as the third parameter to |
|
** the xAccess method of an [sqlite3_vfs] object. They determine |
|
** what kind of permissions the xAccess method is looking for. |
|
** With SQLITE_ACCESS_EXISTS, the xAccess method |
|
** simply checks whether the file exists. |
|
** With SQLITE_ACCESS_READWRITE, the xAccess method |
|
** checks whether the named directory is both readable and writable |
|
** (in other words, if files can be added, removed, and renamed within |
|
** the directory). |
|
** The SQLITE_ACCESS_READWRITE constant is currently used only by the |
|
** [temp_store_directory pragma], though this could change in a future |
|
** release of SQLite. |
|
** With SQLITE_ACCESS_READ, the xAccess method |
|
** checks whether the file is readable. The SQLITE_ACCESS_READ constant is |
|
** currently unused, though it might be used in a future release of |
|
** SQLite. |
|
*/ |
|
#define SQLITE_ACCESS_EXISTS 0 |
|
#define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */ |
|
#define SQLITE_ACCESS_READ 2 /* Unused */ |
|
|
|
/* |
|
** CAPI3REF: Flags for the xShmLock VFS method |
|
** |
|
** These integer constants define the various locking operations |
|
** allowed by the xShmLock method of [sqlite3_io_methods]. The |
|
** following are the only legal combinations of flags to the |
|
** xShmLock method: |
|
** |
|
** <ul> |
|
** <li> SQLITE_SHM_LOCK | SQLITE_SHM_SHARED |
|
** <li> SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE |
|
** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED |
|
** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE |
|
** </ul> |
|
** |
|
** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as |
|
** was given on the corresponding lock. |
|
** |
|
** The xShmLock method can transition between unlocked and SHARED or |
|
** between unlocked and EXCLUSIVE. It cannot transition between SHARED |
|
** and EXCLUSIVE. |
|
*/ |
|
#define SQLITE_SHM_UNLOCK 1 |
|
#define SQLITE_SHM_LOCK 2 |
|
#define SQLITE_SHM_SHARED 4 |
|
#define SQLITE_SHM_EXCLUSIVE 8 |
|
|
|
/* |
|
** CAPI3REF: Maximum xShmLock index |
|
** |
|
** The xShmLock method on [sqlite3_io_methods] may use values |
|
** between 0 and this upper bound as its "offset" argument. |
|
** The SQLite core will never attempt to acquire or release a |
|
** lock outside of this range |
|
*/ |
|
#define SQLITE_SHM_NLOCK 8 |
|
|
|
|
|
/* |
|
** CAPI3REF: Initialize The SQLite Library |
|
** |
|
** ^The sqlite3_initialize() routine initializes the |
|
** SQLite library. ^The sqlite3_shutdown() routine |
|
** deallocates any resources that were allocated by sqlite3_initialize(). |
|
** These routines are designed to aid in process initialization and |
|
** shutdown on embedded systems. Workstation applications using |
|
** SQLite normally do not need to invoke either of these routines. |
|
** |
|
** A call to sqlite3_initialize() is an "effective" call if it is |
|
** the first time sqlite3_initialize() is invoked during the lifetime of |
|
** the process, or if it is the first time sqlite3_initialize() is invoked |
|
** following a call to sqlite3_shutdown(). ^(Only an effective call |
|
** of sqlite3_initialize() does any initialization. All other calls |
|
** are harmless no-ops.)^ |
|
** |
|
** A call to sqlite3_shutdown() is an "effective" call if it is the first |
|
** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only |
|
** an effective call to sqlite3_shutdown() does any deinitialization. |
|
** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^ |
|
** |
|
** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown() |
|
** is not. The sqlite3_shutdown() interface must only be called from a |
|
** single thread. All open [database connections] must be closed and all |
|
** other SQLite resources must be deallocated prior to invoking |
|
** sqlite3_shutdown(). |
|
** |
|
** Among other things, ^sqlite3_initialize() will invoke |
|
** sqlite3_os_init(). Similarly, ^sqlite3_shutdown() |
|
** will invoke sqlite3_os_end(). |
|
** |
|
** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success. |
|
** ^If for some reason, sqlite3_initialize() is unable to initialize |
|
** the library (perhaps it is unable to allocate a needed resource such |
|
** as a mutex) it returns an [error code] other than [SQLITE_OK]. |
|
** |
|
** ^The sqlite3_initialize() routine is called internally by many other |
|
** SQLite interfaces so that an application usually does not need to |
|
** invoke sqlite3_initialize() directly. For example, [sqlite3_open()] |
|
** calls sqlite3_initialize() so the SQLite library will be automatically |
|
** initialized when [sqlite3_open()] is called if it has not be initialized |
|
** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT] |
|
** compile-time option, then the automatic calls to sqlite3_initialize() |
|
** are omitted and the application must call sqlite3_initialize() directly |
|
** prior to using any other SQLite interface. For maximum portability, |
|
** it is recommended that applications always invoke sqlite3_initialize() |
|
** directly prior to using any other SQLite interface. Future releases |
|
** of SQLite may require this. In other words, the behavior exhibited |
|
** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the |
|
** default behavior in some future release of SQLite. |
|
** |
|
** The sqlite3_os_init() routine does operating-system specific |
|
** initialization of the SQLite library. The sqlite3_os_end() |
|
** routine undoes the effect of sqlite3_os_init(). Typical tasks |
|
** performed by these routines include allocation or deallocation |
|
** of static resources, initialization of global variables, |
|
** setting up a default [sqlite3_vfs] module, or setting up |
|
** a default configuration using [sqlite3_config()]. |
|
** |
|
** The application should never invoke either sqlite3_os_init() |
|
** or sqlite3_os_end() directly. The application should only invoke |
|
** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init() |
|
** interface is called automatically by sqlite3_initialize() and |
|
** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate |
|
** implementations for sqlite3_os_init() and sqlite3_os_end() |
|
** are built into SQLite when it is compiled for Unix, Windows, or OS/2. |
|
** When [custom builds | built for other platforms] |
|
** (using the [SQLITE_OS_OTHER=1] compile-time |
|
** option) the application must supply a suitable implementation for |
|
** sqlite3_os_init() and sqlite3_os_end(). An application-supplied |
|
** implementation of sqlite3_os_init() or sqlite3_os_end() |
|
** must return [SQLITE_OK] on success and some other [error code] upon |
|
** failure. |
|
*/ |
|
SQLITE_API int sqlite3_initialize(void); |
|
SQLITE_API int sqlite3_shutdown(void); |
|
SQLITE_API int sqlite3_os_init(void); |
|
SQLITE_API int sqlite3_os_end(void); |
|
|
|
/* |
|
** CAPI3REF: Configuring The SQLite Library |
|
** |
|
** The sqlite3_config() interface is used to make global configuration |
|
** changes to SQLite in order to tune SQLite to the specific needs of |
|
** the application. The default configuration is recommended for most |
|
** applications and so this routine is usually not necessary. It is |
|
** provided to support rare applications with unusual needs. |
|
** |
|
** <b>The sqlite3_config() interface is not threadsafe. The application |
|
** must ensure that no other SQLite interfaces are invoked by other |
|
** threads while sqlite3_config() is running.</b> |
|
** |
|
** The sqlite3_config() interface |
|
** may only be invoked prior to library initialization using |
|
** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()]. |
|
** ^If sqlite3_config() is called after [sqlite3_initialize()] and before |
|
** [sqlite3_shutdown()] then it will return SQLITE_MISUSE. |
|
** Note, however, that ^sqlite3_config() can be called as part of the |
|
** implementation of an application-defined [sqlite3_os_init()]. |
|
** |
|
** The first argument to sqlite3_config() is an integer |
|
** [configuration option] that determines |
|
** what property of SQLite is to be configured. Subsequent arguments |
|
** vary depending on the [configuration option] |
|
** in the first argument. |
|
** |
|
** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK]. |
|
** ^If the option is unknown or SQLite is unable to set the option |
|
** then this routine returns a non-zero [error code]. |
|
*/ |
|
SQLITE_API int sqlite3_config(int, ...); |
|
|
|
/* |
|
** CAPI3REF: Configure database connections |
|
** METHOD: sqlite3 |
|
** |
|
** The sqlite3_db_config() interface is used to make configuration |
|
** changes to a [database connection]. The interface is similar to |
|
** [sqlite3_config()] except that the changes apply to a single |
|
** [database connection] (specified in the first argument). |
|
** |
|
** The second argument to sqlite3_db_config(D,V,...) is the |
|
** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code |
|
** that indicates what aspect of the [database connection] is being configured. |
|
** Subsequent arguments vary depending on the configuration verb. |
|
** |
|
** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if |
|
** the call is considered successful. |
|
*/ |
|
SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...); |
|
|
|
/* |
|
** CAPI3REF: Memory Allocation Routines |
|
** |
|
** An instance of this object defines the interface between SQLite |
|
** and low-level memory allocation routines. |
|
** |
|
** This object is used in only one place in the SQLite interface. |
|
** A pointer to an instance of this object is the argument to |
|
** [sqlite3_config()] when the configuration option is |
|
** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC]. |
|
** By creating an instance of this object |
|
** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC]) |
|
** during configuration, an application can specify an alternative |
|
** memory allocation subsystem for SQLite to use for all of its |
|
** dynamic memory needs. |
|
** |
|
** Note that SQLite comes with several [built-in memory allocators] |
|
** that are perfectly adequate for the overwhelming majority of applications |
|
** and that this object is only useful to a tiny minority of applications |
|
** with specialized memory allocation requirements. This object is |
|
** also used during testing of SQLite in order to specify an alternative |
|
** memory allocator that simulates memory out-of-memory conditions in |
|
** order to verify that SQLite recovers gracefully from such |
|
** conditions. |
|
** |
|
** The xMalloc, xRealloc, and xFree methods must work like the |
|
** malloc(), realloc() and free() functions from the standard C library. |
|
** ^SQLite guarantees that the second argument to |
|
** xRealloc is always a value returned by a prior call to xRoundup. |
|
** |
|
** xSize should return the allocated size of a memory allocation |
|
** previously obtained from xMalloc or xRealloc. The allocated size |
|
** is always at least as big as the requested size but may be larger. |
|
** |
|
** The xRoundup method returns what would be the allocated size of |
|
** a memory allocation given a particular requested size. Most memory |
|
** allocators round up memory allocations at least to the next multiple |
|
** of 8. Some allocators round up to a larger multiple or to a power of 2. |
|
** Every memory allocation request coming in through [sqlite3_malloc()] |
|
** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0, |
|
** that causes the corresponding memory allocation to fail. |
|
** |
|
** The xInit method initializes the memory allocator. For example, |
|
** it might allocate any require mutexes or initialize internal data |
|
** structures. The xShutdown method is invoked (indirectly) by |
|
** [sqlite3_shutdown()] and should deallocate any resources acquired |
|
** by xInit. The pAppData pointer is used as the only parameter to |
|
** xInit and xShutdown. |
|
** |
|
** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes |
|
** the xInit method, so the xInit method need not be threadsafe. The |
|
** xShutdown method is only called from [sqlite3_shutdown()] so it does |
|
** not need to be threadsafe either. For all other methods, SQLite |
|
** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the |
|
** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which |
|
** it is by default) and so the methods are automatically serialized. |
|
** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other |
|
** methods must be threadsafe or else make their own arrangements for |
|
** serialization. |
|
** |
|
** SQLite will never invoke xInit() more than once without an intervening |
|
** call to xShutdown(). |
|
*/ |
|
typedef struct sqlite3_mem_methods sqlite3_mem_methods; |
|
struct sqlite3_mem_methods { |
|
void *(*xMalloc)(int); /* Memory allocation function */ |
|
void (*xFree)(void*); /* Free a prior allocation */ |
|
void *(*xRealloc)(void*,int); /* Resize an allocation */ |
|
int (*xSize)(void*); /* Return the size of an allocation */ |
|
int (*xRoundup)(int); /* Round up request size to allocation size */ |
|
int (*xInit)(void*); /* Initialize the memory allocator */ |
|
void (*xShutdown)(void*); /* Deinitialize the memory allocator */ |
|
void *pAppData; /* Argument to xInit() and xShutdown() */ |
|
}; |
|
|
|
/* |
|
** CAPI3REF: Configuration Options |
|
** KEYWORDS: {configuration option} |
|
** |
|
** These constants are the available integer configuration options that |
|
** can be passed as the first argument to the [sqlite3_config()] interface. |
|
** |
|
** New configuration options may be added in future releases of SQLite. |
|
** Existing configuration options might be discontinued. Applications |
|
** should check the return code from [sqlite3_config()] to make sure that |
|
** the call worked. The [sqlite3_config()] interface will return a |
|
** non-zero [error code] if a discontinued or unsupported configuration option |
|
** is invoked. |
|
** |
|
** <dl> |
|
** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt> |
|
** <dd>There are no arguments to this option. ^This option sets the |
|
** [threading mode] to Single-thread. In other words, it disables |
|
** all mutexing and puts SQLite into a mode where it can only be used |
|
** by a single thread. ^If SQLite is compiled with |
|
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then |
|
** it is not possible to change the [threading mode] from its default |
|
** value of Single-thread and so [sqlite3_config()] will return |
|
** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD |
|
** configuration option.</dd> |
|
** |
|
** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt> |
|
** <dd>There are no arguments to this option. ^This option sets the |
|
** [threading mode] to Multi-thread. In other words, it disables |
|
** mutexing on [database connection] and [prepared statement] objects. |
|
** The application is responsible for serializing access to |
|
** [database connections] and [prepared statements]. But other mutexes |
|
** are enabled so that SQLite will be safe to use in a multi-threaded |
|
** environment as long as no two threads attempt to use the same |
|
** [database connection] at the same time. ^If SQLite is compiled with |
|
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then |
|
** it is not possible to set the Multi-thread [threading mode] and |
|
** [sqlite3_config()] will return [SQLITE_ERROR] if called with the |
|
** SQLITE_CONFIG_MULTITHREAD configuration option.</dd> |
|
** |
|
** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt> |
|
** <dd>There are no arguments to this option. ^This option sets the |
|
** [threading mode] to Serialized. In other words, this option enables |
|
** all mutexes including the recursive |
|
** mutexes on [database connection] and [prepared statement] objects. |
|
** In this mode (which is the default when SQLite is compiled with |
|
** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access |
|
** to [database connections] and [prepared statements] so that the |
|
** application is free to use the same [database connection] or the |
|
** same [prepared statement] in different threads at the same time. |
|
** ^If SQLite is compiled with |
|
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then |
|
** it is not possible to set the Serialized [threading mode] and |
|
** [sqlite3_config()] will return [SQLITE_ERROR] if called with the |
|
** SQLITE_CONFIG_SERIALIZED configuration option.</dd> |
|
** |
|
** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt> |
|
** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is |
|
** a pointer to an instance of the [sqlite3_mem_methods] structure. |
|
** The argument specifies |
|
** alternative low-level memory allocation routines to be used in place of |
|
** the memory allocation routines built into SQLite.)^ ^SQLite makes |
|
** its own private copy of the content of the [sqlite3_mem_methods] structure |
|
** before the [sqlite3_config()] call returns.</dd> |
|
** |
|
** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt> |
|
** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which |
|
** is a pointer to an instance of the [sqlite3_mem_methods] structure. |
|
** The [sqlite3_mem_methods] |
|
** structure is filled with the currently defined memory allocation routines.)^ |
|
** This option can be used to overload the default memory allocation |
|
** routines with a wrapper that simulations memory allocation failure or |
|
** tracks memory usage, for example. </dd> |
|
** |
|
** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt> |
|
** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int, |
|
** interpreted as a boolean, which enables or disables the collection of |
|
** memory allocation statistics. ^(When memory allocation statistics are |
|
** disabled, the following SQLite interfaces become non-operational: |
|
** <ul> |
|
** <li> [sqlite3_memory_used()] |
|
** <li> [sqlite3_memory_highwater()] |
|
** <li> [sqlite3_soft_heap_limit64()] |
|
** <li> [sqlite3_status64()] |
|
** </ul>)^ |
|
** ^Memory allocation statistics are enabled by default unless SQLite is |
|
** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory |
|
** allocation statistics are disabled by default. |
|
** </dd> |
|
** |
|
** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt> |
|
** <dd> ^The SQLITE_CONFIG_SCRATCH option specifies a static memory buffer |
|
** that SQLite can use for scratch memory. ^(There are three arguments |
|
** to SQLITE_CONFIG_SCRATCH: A pointer an 8-byte |
|
** aligned memory buffer from which the scratch allocations will be |
|
** drawn, the size of each scratch allocation (sz), |
|
** and the maximum number of scratch allocations (N).)^ |
|
** The first argument must be a pointer to an 8-byte aligned buffer |
|
** of at least sz*N bytes of memory. |
|
** ^SQLite will not use more than one scratch buffers per thread. |
|
** ^SQLite will never request a scratch buffer that is more than 6 |
|
** times the database page size. |
|
** ^If SQLite needs needs additional |
|
** scratch memory beyond what is provided by this configuration option, then |
|
** [sqlite3_malloc()] will be used to obtain the memory needed.<p> |
|
** ^When the application provides any amount of scratch memory using |
|
** SQLITE_CONFIG_SCRATCH, SQLite avoids unnecessary large |
|
** [sqlite3_malloc|heap allocations]. |
|
** This can help [Robson proof|prevent memory allocation failures] due to heap |
|
** fragmentation in low-memory embedded systems. |
|
** </dd> |
|
** |
|
** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt> |
|
** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool |
|
** that SQLite can use for the database page cache with the default page |
|
** cache implementation. |
|
** This configuration option is a no-op if an application-define page |
|
** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2]. |
|
** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to |
|
** 8-byte aligned memory (pMem), the size of each page cache line (sz), |
|
** and the number of cache lines (N). |
|
** The sz argument should be the size of the largest database page |
|
** (a power of two between 512 and 65536) plus some extra bytes for each |
|
** page header. ^The number of extra bytes needed by the page header |
|
** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ]. |
|
** ^It is harmless, apart from the wasted memory, |
|
** for the sz parameter to be larger than necessary. The pMem |
|
** argument must be either a NULL pointer or a pointer to an 8-byte |
|
** aligned block of memory of at least sz*N bytes, otherwise |
|
** subsequent behavior is undefined. |
|
** ^When pMem is not NULL, SQLite will strive to use the memory provided |
|
** to satisfy page cache needs, falling back to [sqlite3_malloc()] if |
|
** a page cache line is larger than sz bytes or if all of the pMem buffer |
|
** is exhausted. |
|
** ^If pMem is NULL and N is non-zero, then each database connection |
|
** does an initial bulk allocation for page cache memory |
|
** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or |
|
** of -1024*N bytes if N is negative, . ^If additional |
|
** page cache memory is needed beyond what is provided by the initial |
|
** allocation, then SQLite goes to [sqlite3_malloc()] separately for each |
|
** additional cache line. </dd> |
|
** |
|
** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt> |
|
** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer |
|
** that SQLite will use for all of its dynamic memory allocation needs |
|
** beyond those provided for by [SQLITE_CONFIG_SCRATCH] and |
|
** [SQLITE_CONFIG_PAGECACHE]. |
|
** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled |
|
** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns |
|
** [SQLITE_ERROR] if invoked otherwise. |
|
** ^There are three arguments to SQLITE_CONFIG_HEAP: |
|
** An 8-byte aligned pointer to the memory, |
|
** the number of bytes in the memory buffer, and the minimum allocation size. |
|
** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts |
|
** to using its default memory allocator (the system malloc() implementation), |
|
** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the |
|
** memory pointer is not NULL then the alternative memory |
|
** allocator is engaged to handle all of SQLites memory allocation needs. |
|
** The first pointer (the memory pointer) must be aligned to an 8-byte |
|
** boundary or subsequent behavior of SQLite will be undefined. |
|
** The minimum allocation size is capped at 2**12. Reasonable values |
|
** for the minimum allocation size are 2**5 through 2**8.</dd> |
|
** |
|
** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt> |
|
** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a |
|
** pointer to an instance of the [sqlite3_mutex_methods] structure. |
|
** The argument specifies alternative low-level mutex routines to be used |
|
** in place the mutex routines built into SQLite.)^ ^SQLite makes a copy of |
|
** the content of the [sqlite3_mutex_methods] structure before the call to |
|
** [sqlite3_config()] returns. ^If SQLite is compiled with |
|
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then |
|
** the entire mutexing subsystem is omitted from the build and hence calls to |
|
** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will |
|
** return [SQLITE_ERROR].</dd> |
|
** |
|
** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt> |
|
** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which |
|
** is a pointer to an instance of the [sqlite3_mutex_methods] structure. The |
|
** [sqlite3_mutex_methods] |
|
** structure is filled with the currently defined mutex routines.)^ |
|
** This option can be used to overload the default mutex allocation |
|
** routines with a wrapper used to track mutex usage for performance |
|
** profiling or testing, for example. ^If SQLite is compiled with |
|
** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then |
|
** the entire mutexing subsystem is omitted from the build and hence calls to |
|
** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will |
|
** return [SQLITE_ERROR].</dd> |
|
** |
|
** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt> |
|
** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine |
|
** the default size of lookaside memory on each [database connection]. |
|
** The first argument is the |
|
** size of each lookaside buffer slot and the second is the number of |
|
** slots allocated to each database connection.)^ ^(SQLITE_CONFIG_LOOKASIDE |
|
** sets the <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE] |
|
** option to [sqlite3_db_config()] can be used to change the lookaside |
|
** configuration on individual connections.)^ </dd> |
|
** |
|
** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt> |
|
** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is |
|
** a pointer to an [sqlite3_pcache_methods2] object. This object specifies |
|
** the interface to a custom page cache implementation.)^ |
|
** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd> |
|
** |
|
** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt> |
|
** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which |
|
** is a pointer to an [sqlite3_pcache_methods2] object. SQLite copies of |
|
** the current page cache implementation into that object.)^ </dd> |
|
** |
|
** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt> |
|
** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite |
|
** global [error log]. |
|
** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a |
|
** function with a call signature of void(*)(void*,int,const char*), |
|
** and a pointer to void. ^If the function pointer is not NULL, it is |
|
** invoked by [sqlite3_log()] to process each logging event. ^If the |
|
** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op. |
|
** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is |
|
** passed through as the first parameter to the application-defined logger |
|
** function whenever that function is invoked. ^The second parameter to |
|
** the logger function is a copy of the first parameter to the corresponding |
|
** [sqlite3_log()] call and is intended to be a [result code] or an |
|
** [extended result code]. ^The third parameter passed to the logger is |
|
** log message after formatting via [sqlite3_snprintf()]. |
|
** The SQLite logging interface is not reentrant; the logger function |
|
** supplied by the application must not invoke any SQLite interface. |
|
** In a multi-threaded application, the application-defined logger |
|
** function must be threadsafe. </dd> |
|
** |
|
** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI |
|
** <dd>^(The SQLITE_CONFIG_URI option takes a single argument of type int. |
|
** If non-zero, then URI handling is globally enabled. If the parameter is zero, |
|
** then URI handling is globally disabled.)^ ^If URI handling is globally |
|
** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()], |
|
** [sqlite3_open16()] or |
|
** specified as part of [ATTACH] commands are interpreted as URIs, regardless |
|
** of whether or not the [SQLITE_OPEN_URI] flag is set when the database |
|
** connection is opened. ^If it is globally disabled, filenames are |
|
** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the |
|
** database connection is opened. ^(By default, URI handling is globally |
|
** disabled. The default value may be changed by compiling with the |
|
** [SQLITE_USE_URI] symbol defined.)^ |
|
** |
|
** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN |
|
** <dd>^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer |
|
** argument which is interpreted as a boolean in order to enable or disable |
|
** the use of covering indices for full table scans in the query optimizer. |
|
** ^The default setting is determined |
|
** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on" |
|
** if that compile-time option is omitted. |
|
** The ability to disable the use of covering indices for full table scans |
|
** is because some incorrectly coded legacy applications might malfunction |
|
** when the optimization is enabled. Providing the ability to |
|
** disable the optimization allows the older, buggy application code to work |
|
** without change even with newer versions of SQLite. |
|
** |
|
** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]] |
|
** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE |
|
** <dd> These options are obsolete and should not be used by new code. |
|
** They are retained for backwards compatibility but are now no-ops. |
|
** </dd> |
|
** |
|
** [[SQLITE_CONFIG_SQLLOG]] |
|
** <dt>SQLITE_CONFIG_SQLLOG |
|
** <dd>This option is only available if sqlite is compiled with the |
|
** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should |
|
** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int). |
|
** The second should be of type (void*). The callback is invoked by the library |
|
** in three separate circumstances, identified by the value passed as the |
|
** fourth parameter. If the fourth parameter is 0, then the database connection |
|
** passed as the second argument has just been opened. The third argument |
|
** points to a buffer containing the name of the main database file. If the |
|
** fourth parameter is 1, then the SQL statement that the third parameter |
|
** points to has just been executed. Or, if the fourth parameter is 2, then |
|
** the connection being passed as the second parameter is being closed. The |
|
** third parameter is passed NULL In this case. An example of using this |
|
** configuration option can be seen in the "test_sqllog.c" source file in |
|
** the canonical SQLite source tree.</dd> |
|
** |
|
** [[SQLITE_CONFIG_MMAP_SIZE]] |
|
** <dt>SQLITE_CONFIG_MMAP_SIZE |
|
** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values |
|
** that are the default mmap size limit (the default setting for |
|
** [PRAGMA mmap_size]) and the maximum allowed mmap size limit. |
|
** ^The default setting can be overridden by each database connection using |
|
** either the [PRAGMA mmap_size] command, or by using the |
|
** [SQLITE_FCNTL_MMAP_SIZE] file control. ^(The maximum allowed mmap size |
|
** will be silently truncated if necessary so that it does not exceed the |
|
** compile-time maximum mmap size set by the |
|
** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^ |
|
** ^If either argument to this option is negative, then that argument is |
|
** changed to its compile-time default. |
|
** |
|
** [[SQLITE_CONFIG_WIN32_HEAPSIZE]] |
|
** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE |
|
** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is |
|
** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro |
|
** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value |
|
** that specifies the maximum size of the created heap. |
|
** |
|
** [[SQLITE_CONFIG_PCACHE_HDRSZ]] |
|
** <dt>SQLITE_CONFIG_PCACHE_HDRSZ |
|
** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which |
|
** is a pointer to an integer and writes into that integer the number of extra |
|
** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE]. |
|
** The amount of extra space required can change depending on the compiler, |
|
** target platform, and SQLite version. |
|
** |
|
** [[SQLITE_CONFIG_PMASZ]] |
|
** <dt>SQLITE_CONFIG_PMASZ |
|
** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which |
|
** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded |
|
** sorter to that integer. The default minimum PMA Size is set by the |
|
** [SQLITE_SORTER_PMASZ] compile-time option. New threads are launched |
|
** to help with sort operations when multithreaded sorting |
|
** is enabled (using the [PRAGMA threads] command) and the amount of content |
|
** to be sorted exceeds the page size times the minimum of the |
|
** [PRAGMA cache_size] setting and this value. |
|
** |
|
** [[SQLITE_CONFIG_STMTJRNL_SPILL]] |
|
** <dt>SQLITE_CONFIG_STMTJRNL_SPILL |
|
** <dd>^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which |
|
** becomes the [statement journal] spill-to-disk threshold. |
|
** [Statement journals] are held in memory until their size (in bytes) |
|
** exceeds this threshold, at which point they are written to disk. |
|
** Or if the threshold is -1, statement journals are always held |
|
** exclusively in memory. |
|
** Since many statement journals never become large, setting the spill |
|
** threshold to a value such as 64KiB can greatly reduce the amount of |
|
** I/O required to support statement rollback. |
|
** The default value for this setting is controlled by the |
|
** [SQLITE_STMTJRNL_SPILL] compile-time option. |
|
** </dl> |
|
*/ |
|
#define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */ |
|
#define SQLITE_CONFIG_MULTITHREAD 2 /* nil */ |
|
#define SQLITE_CONFIG_SERIALIZED 3 /* nil */ |
|
#define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */ |
|
#define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */ |
|
#define SQLITE_CONFIG_SCRATCH 6 /* void*, int sz, int N */ |
|
#define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */ |
|
#define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */ |
|
#define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */ |
|
#define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */ |
|
#define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */ |
|
/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */ |
|
#define SQLITE_CONFIG_LOOKASIDE 13 /* int int */ |
|
#define SQLITE_CONFIG_PCACHE 14 /* no-op */ |
|
#define SQLITE_CONFIG_GETPCACHE 15 /* no-op */ |
|
#define SQLITE_CONFIG_LOG 16 /* xFunc, void* */ |
|
#define SQLITE_CONFIG_URI 17 /* int */ |
|
#define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */ |
|
#define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */ |
|
#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20 /* int */ |
|
#define SQLITE_CONFIG_SQLLOG 21 /* xSqllog, void* */ |
|
#define SQLITE_CONFIG_MMAP_SIZE 22 /* sqlite3_int64, sqlite3_int64 */ |
|
#define SQLITE_CONFIG_WIN32_HEAPSIZE 23 /* int nByte */ |
|
#define SQLITE_CONFIG_PCACHE_HDRSZ 24 /* int *psz */ |
|
#define SQLITE_CONFIG_PMASZ 25 /* unsigned int szPma */ |
|
#define SQLITE_CONFIG_STMTJRNL_SPILL 26 /* int nByte */ |
|
|
|
/* |
|
** CAPI3REF: Database Connection Configuration Options |
|
** |
|
** These constants are the available integer configuration options that |
|
** can be passed as the second argument to the [sqlite3_db_config()] interface. |
|
** |
|
** New configuration options may be added in future releases of SQLite. |
|
** Existing configuration options might be discontinued. Applications |
|
** should check the return code from [sqlite3_db_config()] to make sure that |
|
** the call worked. ^The [sqlite3_db_config()] interface will return a |
|
** non-zero [error code] if a discontinued or unsupported configuration option |
|
** is invoked. |
|
** |
|
** <dl> |
|
** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt> |
|
** <dd> ^This option takes three additional arguments that determine the |
|
** [lookaside memory allocator] configuration for the [database connection]. |
|
** ^The first argument (the third parameter to [sqlite3_db_config()] is a |
|
** pointer to a memory buffer to use for lookaside memory. |
|
** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb |
|
** may be NULL in which case SQLite will allocate the |
|
** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the |
|
** size of each lookaside buffer slot. ^The third argument is the number of |
|
** slots. The size of the buffer in the first argument must be greater than |
|
** or equal to the product of the second and third arguments. The buffer |
|
** must be aligned to an 8-byte boundary. ^If the second argument to |
|
** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally |
|
** rounded down to the next smaller multiple of 8. ^(The lookaside memory |
|
** configuration for a database connection can only be changed when that |
|
** connection is not currently using lookaside memory, or in other words |
|
** when the "current value" returned by |
|
** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero. |
|
** Any attempt to change the lookaside memory configuration when lookaside |
|
** memory is in use leaves the configuration unchanged and returns |
|
** [SQLITE_BUSY].)^</dd> |
|
** |
|
** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt> |
|
** <dd> ^This option is used to enable or disable the enforcement of |
|
** [foreign key constraints]. There should be two additional arguments. |
|
** The first argument is an integer which is 0 to disable FK enforcement, |
|
** positive to enable FK enforcement or negative to leave FK enforcement |
|
** unchanged. The second parameter is a pointer to an integer into which |
|
** is written 0 or 1 to indicate whether FK enforcement is off or on |
|
** following this call. The second parameter may be a NULL pointer, in |
|
** which case the FK enforcement setting is not reported back. </dd> |
|
** |
|
** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt> |
|
** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers]. |
|
** There should be two additional arguments. |
|
** The first argument is an integer which is 0 to disable triggers, |
|
** positive to enable triggers or negative to leave the setting unchanged. |
|
** The second parameter is a pointer to an integer into which |
|
** is written 0 or 1 to indicate whether triggers are disabled or enabled |
|
** following this call. The second parameter may be a NULL pointer, in |
|
** which case the trigger setting is not reported back. </dd> |
|
** |
|
** <dt>SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER</dt> |
|
** <dd> ^This option is used to enable or disable the two-argument |
|
** version of the [fts3_tokenizer()] function which is part of the |
|
** [FTS3] full-text search engine extension. |
|
** There should be two additional arguments. |
|
** The first argument is an integer which is 0 to disable fts3_tokenizer() or |
|
** positive to enable fts3_tokenizer() or negative to leave the setting |
|
** unchanged. |
|
** The second parameter is a pointer to an integer into which |
|
** is written 0 or 1 to indicate whether fts3_tokenizer is disabled or enabled |
|
** following this call. The second parameter may be a NULL pointer, in |
|
** which case the new setting is not reported back. </dd> |
|
** |
|
** <dt>SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION</dt> |
|
** <dd> ^This option is used to enable or disable the [sqlite3_load_extension()] |
|
** interface independently of the [load_extension()] SQL function. |
|
** The [sqlite3_enable_load_extension()] API enables or disables both the |
|
** C-API [sqlite3_load_extension()] and the SQL function [load_extension()]. |
|
** There should be two additional arguments. |
|
** When the first argument to this interface is 1, then only the C-API is |
|
** enabled and the SQL function remains disabled. If the first argument to |
|
** this interface is 0, then both the C-API and the SQL function are disabled. |
|
** If the first argument is -1, then no changes are made to state of either the |
|
** C-API or the SQL function. |
|
** The second parameter is a pointer to an integer into which |
|
** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface |
|
** is disabled or enabled following this call. The second parameter may |
|
** be a NULL pointer, in which case the new setting is not reported back. |
|
** </dd> |
|
** |
|
** <dt>SQLITE_DBCONFIG_MAINDBNAME</dt> |
|
** <dd> ^This option is used to change the name of the "main" database |
|
** schema. ^The sole argument is a pointer to a constant UTF8 string |
|
** which will become the new schema name in place of "main". ^SQLite |
|
** does not make a copy of the new main schema name string, so the application |
|
** must ensure that the argument passed into this DBCONFIG option is unchanged |
|
** until after the database connection closes. |
|
** </dd> |
|
** |
|
** </dl> |
|
*/ |
|
#define SQLITE_DBCONFIG_MAINDBNAME 1000 /* const char* */ |
|
#define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */ |
|
#define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */ |
|
#define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */ |
|
#define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */ |
|
#define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */ |
|
|
|
|
|
/* |
|
** CAPI3REF: Enable Or Disable Extended Result Codes |
|
** METHOD: sqlite3 |
|
** |
|
** ^The sqlite3_extended_result_codes() routine enables or disables the |
|
** [extended result codes] feature of SQLite. ^The extended result |
|
** codes are disabled by default for historical compatibility. |
|
*/ |
|
SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff); |
|
|
|
/* |
|
** CAPI3REF: Last Insert Rowid |
|
** METHOD: sqlite3 |
|
** |
|
** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables) |
|
** has a unique 64-bit signed |
|
** integer key called the [ROWID | "rowid"]. ^The rowid is always available |
|
** as an undeclared column named ROWID, OID, or _ROWID_ as long as those |
|
** names are not also used by explicitly declared columns. ^If |
|
** the table has a column of type [INTEGER PRIMARY KEY] then that column |
|
** is another alias for the rowid. |
|
** |
|
** ^The sqlite3_last_insert_rowid(D) interface returns the [rowid] of the |
|
** most recent successful [INSERT] into a rowid table or [virtual table] |
|
** on database connection D. |
|
** ^Inserts into [WITHOUT ROWID] tables are not recorded. |
|
** ^If no successful [INSERT]s into rowid tables |
|
** have ever occurred on the database connection D, |
|
** then sqlite3_last_insert_rowid(D) returns zero. |
|
** |
|
** ^(If an [INSERT] occurs within a trigger or within a [virtual table] |
|
** method, then this routine will return the [rowid] of the inserted |
|
** row as long as the trigger or virtual table method is running. |
|
** But once the trigger or virtual table method ends, the value returned |
|
** by this routine reverts to what it was before the trigger or virtual |
|
** table method began.)^ |
|
** |
|
** ^An [INSERT] that fails due to a constraint violation is not a |
|
** successful [INSERT] and does not change the value returned by this |
|
** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK, |
|
** and INSERT OR ABORT make no changes to the return value of this |
|
** routine when their insertion fails. ^(When INSERT OR REPLACE |
|
** encounters a constraint violation, it does not fail. The |
|
** INSERT continues to completion after deleting rows that caused |
|
** the constraint problem so INSERT OR REPLACE will always change |
|
** the return value of this interface.)^ |
|
** |
|
** ^For the purposes of this routine, an [INSERT] is considered to |
|
** be successful even if it is subsequently rolled back. |
|
** |
|
** This function is accessible to SQL statements via the |
|
** [last_insert_rowid() SQL function]. |
|
** |
|
** If a separate thread performs a new [INSERT] on the same |
|
** database connection while the [sqlite3_last_insert_rowid()] |
|
** function is running and thus changes the last insert [rowid], |
|
** then the value returned by [sqlite3_last_insert_rowid()] is |
|
** unpredictable and might not equal either the old or the new |
|
** last insert [rowid]. |
|
*/ |
|
SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*); |
|
|
|
/* |
|
** CAPI3REF: Count The Number Of Rows Modified |
|
** METHOD: sqlite3 |
|
** |
|
** ^This function returns the number of rows modified, inserted or |
|
** deleted by the most recently completed INSERT, UPDATE or DELETE |
|
** statement on the database connection specified by the only parameter. |
|
** ^Executing any other type of SQL statement does not modify the value |
|
** returned by this function. |
|
** |
|
** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are |
|
** considered - auxiliary changes caused by [CREATE TRIGGER | triggers], |
|
** [foreign key actions] or [REPLACE] constraint resolution are not counted. |
|
** |
|
** Changes to a view that are intercepted by |
|
** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value |
|
** returned by sqlite3_changes() immediately after an INSERT, UPDATE or |
|
** DELETE statement run on a view is always zero. Only changes made to real |
|
** tables are counted. |
|
** |
|
** Things are more complicated if the sqlite3_changes() function is |
|
** executed while a trigger program is running. This may happen if the |
|
** program uses the [changes() SQL function], or if some other callback |
|
** function invokes sqlite3_changes() directly. Essentially: |
|
** |
|
** <ul> |
|
** <li> ^(Before entering a trigger program the value returned by |
|
** sqlite3_changes() function is saved. After the trigger program |
|
** has finished, the original value is restored.)^ |
|
** |
|
** <li> ^(Within a trigger program each INSERT, UPDATE and DELETE |
|
** statement sets the value returned by sqlite3_changes() |
|
** upon completion as normal. Of course, this value will not include |
|
** any changes performed by sub-triggers, as the sqlite3_changes() |
|
** value will be saved and restored after each sub-trigger has run.)^ |
|
** </ul> |
|
** |
|
** ^This means that if the changes() SQL function (or similar) is used |
|
** by the first INSERT, UPDATE or DELETE statement within a trigger, it |
|
** returns the value as set when the calling statement began executing. |
|
** ^If it is used by the second or subsequent such statement within a trigger |
|
** program, the value returned reflects the number of rows modified by the |
|
** previous INSERT, UPDATE or DELETE statement within the same trigger. |
|
** |
|
** See also the [sqlite3_total_changes()] interface, the |
|
** [count_changes pragma], and the [changes() SQL function]. |
|
** |
|
** If a separate thread makes changes on the same database connection |
|
** while [sqlite3_changes()] is running then the value returned |
|
** is unpredictable and not meaningful. |
|
*/ |
|
SQLITE_API int sqlite3_changes(sqlite3*); |
|
|
|
/* |
|
** CAPI3REF: Total Number Of Rows Modified |
|
** METHOD: sqlite3 |
|
** |
|
** ^This function returns the total number of rows inserted, modified or |
|
** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed |
|
** since the database connection was opened, including those executed as |
|
** part of trigger programs. ^Executing any other type of SQL statement |
|
** does not affect the value returned by sqlite3_total_changes(). |
|
** |
|
** ^Changes made as part of [foreign key actions] are included in the |
|
** count, but those made as part of REPLACE constraint resolution are |
|
** not. ^Changes to a view that are intercepted by INSTEAD OF triggers |
|
** are not counted. |
|
** |
|
** See also the [sqlite3_changes()] interface, the |
|
** [count_changes pragma], and the [total_changes() SQL function]. |
|
** |
|
** If a separate thread makes changes on the same database connection |
|
** while [sqlite3_total_changes()] is running then the value |
|
** returned is unpredictable and not meaningful. |
|
*/ |
|
SQLITE_API int sqlite3_total_changes(sqlite3*); |
|
|
|
/* |
|
** CAPI3REF: Interrupt A Long-Running Query |
|
** METHOD: sqlite3 |
|
** |
|
** ^This function causes any pending database operation to abort and |
|
** return at its earliest opportunity. This routine is typically |
|
** called in response to a user action such as pressing "Cancel" |
|
** or Ctrl-C where the user wants a long query operation to halt |
|
** immediately. |
|
** |
|
** ^It is safe to call this routine from a thread different from the |
|
** thread that is currently running the database operation. But it |
|
** is not safe to call this routine with a [database connection] that |
|
** is closed or might close before sqlite3_interrupt() returns. |
|
** |
|
** ^If an SQL operation is very nearly finished at the time when |
|
** sqlite3_interrupt() is called, then it might not have an opportunity |
|
** to be interrupted and might continue to completion. |
|
** |
|
** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT]. |
|
** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE |
|
** that is inside an explicit transaction, then the entire transaction |
|
** will be rolled back automatically. |
|
** |
|
** ^The sqlite3_interrupt(D) call is in effect until all currently running |
|
** SQL statements on [database connection] D complete. ^Any new SQL statements |
|
** that are started after the sqlite3_interrupt() call and before the |
|
** running statements reaches zero are interrupted as if they had been |
|
** running prior to the sqlite3_interrupt() call. ^New SQL statements |
|
** that are started after the running statement count reaches zero are |
|
** not effected by the sqlite3_interrupt(). |
|
** ^A call to sqlite3_interrupt(D) that occurs when there are no running |
|
** SQL statements is a no-op and has no effect on SQL statements |
|
** that are started after the sqlite3_interrupt() call returns. |
|
** |
|
** If the database connection closes while [sqlite3_interrupt()] |
|
** is running then bad things will likely happen. |
|
*/ |
|
SQLITE_API void sqlite3_interrupt(sqlite3*); |
|
|
|
/* |
|
** CAPI3REF: Determine If An SQL Statement Is Complete |
|
** |
|
** These routines are useful during command-line input to determine if the |
|
** currently entered text seems to form a complete SQL statement or |
|
** if additional input is needed before sending the text into |
|
** SQLite for parsing. ^These routines return 1 if the input string |
|
** appears to be a complete SQL statement. ^A statement is judged to be |
|
** complete if it ends with a semicolon token and is not a prefix of a |
|
** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within |
|
** string literals or quoted identifier names or comments are not |
|
** independent tokens (they are part of the token in which they are |
|
** embedded) and thus do not count as a statement terminator. ^Whitespace |
|
** and comments that follow the final semicolon are ignored. |
|
** |
|
** ^These routines return 0 if the statement is incomplete. ^If a |
|
** memory allocation fails, then SQLITE_NOMEM is returned. |
|
** |
|
** ^These routines do not parse the SQL statements thus |
|
** will not detect syntactically incorrect SQL. |
|
** |
|
** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior |
|
** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked |
|
** automatically by sqlite3_complete16(). If that initialization fails, |
|
** then the return value from sqlite3_complete16() will be non-zero |
|
** regardless of whether or not the input SQL is complete.)^ |
|
** |
|
** The input to [sqlite3_complete()] must be a zero-terminated |
|
** UTF-8 string. |
|
** |
|
** The input to [sqlite3_complete16()] must be a zero-terminated |
|
** UTF-16 string in native byte order. |
|
*/ |
|
SQLITE_API int sqlite3_complete(const char *sql); |
|
SQLITE_API int sqlite3_complete16(const void *sql); |
|
|
|
/* |
|
** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors |
|
** KEYWORDS: {busy-handler callback} {busy handler} |
|
** METHOD: sqlite3 |
|
** |
|
** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X |
|
** that might be invoked with argument P whenever |
|
** an attempt is made to access a database table associated with |
|
** [database connection] D when another thread |
|
** or process has the table locked. |
|
** The sqlite3_busy_handler() interface is used to implement |
|
** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout]. |
|
** |
|
** ^If the busy callback is NULL, then [SQLITE_BUSY] |
|
** is returned immediately upon encountering the lock. ^If the busy callback |
|
** is not NULL, then the callback might be invoked with two arguments. |
|
** |
|
** ^The first argument to the busy handler is a copy of the void* pointer which |
|
** is the third argument to sqlite3_busy_handler(). ^The second argument to |
|
** the busy handler callback is the number of times that the busy handler has |
|
** been invoked previously for the same locking event. ^If the |
|
** busy callback returns 0, then no additional attempts are made to |
|
** access the database and [SQLITE_BUSY] is returned |
|
** to the application. |
|
** ^If the callback returns non-zero, then another attempt |
|
** is made to access the database and the cycle repeats. |
|
** |
|
** The presence of a busy handler does not guarantee that it will be invoked |
|
** when there is lock contention. ^If SQLite determines that invoking the busy |
|
** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY] |
|
** to the application instead of invoking the |
|
** busy handler. |
|
** Consider a scenario where one process is holding a read lock that |
|
** it is trying to promote to a reserved lock and |
|
** a second process is holding a reserved lock that it is trying |
|
** to promote to an exclusive lock. The first process cannot proceed |
|
** because it is blocked by the second and the second process cannot |
|
** proceed because it is blocked by the first. If both processes |
|
** invoke the busy handlers, neither will make any progress. Therefore, |
|
** SQLite returns [SQLITE_BUSY] for the first process, hoping that this |
|
** will induce the first process to release its read lock and allow |
|
** the second process to proceed. |
|
** |
|
** ^The default busy callback is NULL. |
|
** |
|
** ^(There can only be a single busy handler defined for each |
|
** [database connection]. Setting a new busy handler clears any |
|
** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()] |
|
** or evaluating [PRAGMA busy_timeout=N] will change the |
|
** busy handler and thus clear any previously set busy handler. |
|
** |
|
** The busy callback should not take any actions which modify the |
|
** database connection that invoked the busy handler. In other words, |
|
** the busy handler is not reentrant. Any such actions |
|
** result in undefined behavior. |
|
** |
|
** A busy handler must not close the database connection |
|
** or [prepared statement] that invoked the busy handler. |
|
*/ |
|
SQLITE_API int sqlite3_busy_handler(sqlite3*,int(*)(void*,int),void*); |
|
|
|
/* |
|
** CAPI3REF: Set A Busy Timeout |
|
** METHOD: sqlite3 |
|
** |
|
** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps |
|
** for a specified amount of time when a table is locked. ^The handler |
|
** will sleep multiple times until at least "ms" milliseconds of sleeping |
|
** have accumulated. ^After at least "ms" milliseconds of sleeping, |
|
** the handler returns 0 which causes [sqlite3_step()] to return |
|
** [SQLITE_BUSY]. |
|
** |
|
** ^Calling this routine with an argument less than or equal to zero |
|
** turns off all busy handlers. |
|
** |
|
** ^(There can only be a single busy handler for a particular |
|
** [database connection] at any given moment. If another busy handler |
|
** was defined (using [sqlite3_busy_handler()]) prior to calling |
|
** this routine, that other busy handler is cleared.)^ |
|
** |
|
** See also: [PRAGMA busy_timeout] |
|
*/ |
|
SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms); |
|
|
|
/* |
|
** CAPI3REF: Convenience Routines For Running Queries |
|
** METHOD: sqlite3 |
|
** |
|
** This is a legacy interface that is preserved for backwards compatibility. |
|
** Use of this interface is not recommended. |
|
** |
|
** Definition: A <b>result table</b> is memory data structure created by the |
|
** [sqlite3_get_table()] interface. A result table records the |
|
** complete query results from one or more queries. |
|
** |
|
** The table conceptually has a number of rows and columns. But |
|
** these numbers are not part of the result table itself. These |
|
** numbers are obtained separately. Let N be the number of rows |
|
** and M be the number of columns. |
|
** |
|
** A result table is an array of pointers to zero-terminated UTF-8 strings. |
|
** There are (N+1)*M elements in the array. The first M pointers point |
|
** to zero-terminated strings that contain the names of the columns. |
|
** The remaining entries all point to query results. NULL values result |
|
** in NULL pointers. All other values are in their UTF-8 zero-terminated |
|
** string representation as returned by [sqlite3_column_text()]. |
|
** |
|
** A result table might consist of one or more memory allocations. |
|
** It is not safe to pass a result table directly to [sqlite3_free()]. |
|
** A result table should be deallocated using [sqlite3_free_table()]. |
|
** |
|
** ^(As an example of the result table format, suppose a query result |
|
** is as follows: |
|
** |
|
** <blockquote><pre> |
|
** Name | Age |
|
** ----------------------- |
|
** Alice | 43 |
|
** Bob | 28 |
|
** Cindy | 21 |
|
** </pre></blockquote> |
|
** |
|
** There are two column (M==2) and three rows (N==3). Thus the |
|
** result table has 8 entries. Suppose the result table is stored |
|
** in an array names azResult. Then azResult holds this content: |
|
** |
|
** <blockquote><pre> |
|
** azResult[0] = "Name"; |
|
** azResult[1] = "Age"; |
|
** azResult[2] = "Alice"; |
|
** azResult[3] = "43"; |
|
** azResult[4] = "Bob"; |
|
** azResult[5] = "28"; |
|
** azResult[6] = "Cindy"; |
|
** azResult[7] = "21"; |
|
** </pre></blockquote>)^ |
|
** |
|
** ^The sqlite3_get_table() function evaluates one or more |
|
** semicolon-separated SQL statements in the zero-terminated UTF-8 |
|
** string of its 2nd parameter and returns a result table to the |
|
** pointer given in its 3rd parameter. |
|
** |
|
** After the application has finished with the result from sqlite3_get_table(), |
|
** it must pass the result table pointer to sqlite3_free_table() in order to |
|
** release the memory that was malloced. Because of the way the |
|
** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling |
|
** function must not try to call [sqlite3_free()] directly. Only |
|
** [sqlite3_free_table()] is able to release the memory properly and safely. |
|
** |
|
** The sqlite3_get_table() interface is implemented as a wrapper around |
|
** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access |
|
** to any internal data structures of SQLite. It uses only the public |
|
** interface defined here. As a consequence, errors that occur in the |
|
** wrapper layer outside of the internal [sqlite3_exec()] call are not |
|
** reflected in subsequent calls to [sqlite3_errcode()] or |
|
** [sqlite3_errmsg()]. |
|
*/ |
|
SQLITE_API int sqlite3_get_table( |
|
sqlite3 *db, /* An open database */ |
|
const char *zSql, /* SQL to be evaluated */ |
|
char ***pazResult, /* Results of the query */ |
|
int *pnRow, /* Number of result rows written here */ |
|
int *pnColumn, /* Number of result columns written here */ |
|
char **pzErrmsg /* Error msg written here */ |
|
); |
|
SQLITE_API void sqlite3_free_table(char **result); |
|
|
|
/* |
|
** CAPI3REF: Formatted String Printing Functions |
|
** |
|
** These routines are work-alikes of the "printf()" family of functions |
|
** from the standard C library. |
|
** These routines understand most of the common K&R formatting options, |
|
** plus some additional non-standard formats, detailed below. |
|
** Note that some of the more obscure formatting options from recent |
|
** C-library standards are omitted from this implementation. |
|
** |
|
** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their |
|
** results into memory obtained from [sqlite3_malloc()]. |
|
** The strings returned by these two routines should be |
|
** released by [sqlite3_free()]. ^Both routines return a |
|
** NULL pointer if [sqlite3_malloc()] is unable to allocate enough |
|
** memory to hold the resulting string. |
|
** |
|
** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from |
|
** the standard C library. The result is written into the |
|
** buffer supplied as the second parameter whose size is given by |
|
** the first parameter. Note that the order of the |
|
** first two parameters is reversed from snprintf().)^ This is an |
|
** historical accident that cannot be fixed without breaking |
|
** backwards compatibility. ^(Note also that sqlite3_snprintf() |
|
** returns a pointer to its buffer instead of the number of |
|
** characters actually written into the buffer.)^ We admit that |
|
** the number of characters written would be a more useful return |
|
** value but we cannot change the implementation of sqlite3_snprintf() |
|
** now without breaking compatibility. |
|
** |
|
** ^As long as the buffer size is greater than zero, sqlite3_snprintf() |
|
** guarantees that the buffer is always zero-terminated. ^The first |
|
** parameter "n" is the total size of the buffer, including space for |
|
** the zero terminator. So the longest string that can be completely |
|
** written will be n-1 characters. |
|
** |
|
** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf(). |
|
** |
|
** These routines all implement some additional formatting |
|
** options that are useful for constructing SQL statements. |
|
** All of the usual printf() formatting options apply. In addition, there |
|
** is are "%q", "%Q", "%w" and "%z" options. |
|
** |
|
** ^(The %q option works like %s in that it substitutes a nul-terminated |
|
** string from the argument list. But %q also doubles every '\'' character. |
|
** %q is designed for use inside a string literal.)^ By doubling each '\'' |
|
** character it escapes that character and allows it to be inserted into |
|
** the string. |
|
** |
|
** For example, assume the string variable zText contains text as follows: |
|
** |
|
** <blockquote><pre> |
|
** char *zText = "It's a happy day!"; |
|
** </pre></blockquote> |
|
** |
|
** One can use this text in an SQL statement as follows: |
|
** |
|
** <blockquote><pre> |
|
** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText); |
|
** sqlite3_exec(db, zSQL, 0, 0, 0); |
|
** sqlite3_free(zSQL); |
|
** </pre></blockquote> |
|
** |
|
** Because the %q format string is used, the '\'' character in zText |
|
** is escaped and the SQL generated is as follows: |
|
** |
|
** <blockquote><pre> |
|
** INSERT INTO table1 VALUES('It''s a happy day!') |
|
** </pre></blockquote> |
|
** |
|
** This is correct. Had we used %s instead of %q, the generated SQL |
|
** would have looked like this: |
|
** |
|
** <blockquote><pre> |
|
** INSERT INTO table1 VALUES('It's a happy day!'); |
|
** </pre></blockquote> |
|
** |
|
** This second example is an SQL syntax error. As a general rule you should |
|
** always use %q instead of %s when inserting text into a string literal. |
|
** |
|
** ^(The %Q option works like %q except it also adds single quotes around |
|
** the outside of the total string. Additionally, if the parameter in the |
|
** argument list is a NULL pointer, %Q substitutes the text "NULL" (without |
|
** single quotes).)^ So, for example, one could say: |
|
** |
|
** <blockquote><pre> |
|
** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText); |
|
** sqlite3_exec(db, zSQL, 0, 0, 0); |
|
** sqlite3_free(zSQL); |
|
** </pre></blockquote> |
|
** |
|
** The code above will render a correct SQL statement in the zSQL |
|
** variable even if the zText variable is a NULL pointer. |
|
** |
|
** ^(The "%w" formatting option is like "%q" except that it expects to |
|
** be contained within double-quotes instead of single quotes, and it |
|
** escapes the double-quote character instead of the single-quote |
|
** character.)^ The "%w" formatting option is intended for safely inserting |
|
** table and column names into a constructed SQL statement. |
|
** |
|
** ^(The "%z" formatting option works like "%s" but with the |
|
** addition that after the string has been read and copied into |
|
** the result, [sqlite3_free()] is called on the input string.)^ |
|
*/ |
|
SQLITE_API char *sqlite3_mprintf(const char*,...); |
|
SQLITE_API char *sqlite3_vmprintf(const char*, va_list); |
|
SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...); |
|
SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list); |
|
|
|
/* |
|
** CAPI3REF: Memory Allocation Subsystem |
|
** |
|
** The SQLite core uses these three routines for all of its own |
|
** internal memory allocation needs. "Core" in the previous sentence |
|
** does not include operating-system specific VFS implementation. The |
|
** Windows VFS uses native malloc() and free() for some operations. |
|
** |
|
** ^The sqlite3_malloc() routine returns a pointer to a block |
|
** of memory at least N bytes in length, where N is the parameter. |
|
** ^If sqlite3_malloc() is unable to obtain sufficient free |
|
** memory, it returns a NULL pointer. ^If the parameter N to |
|
** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns |
|
** a NULL pointer. |
|
** |
|
** ^The sqlite3_malloc64(N) routine works just like |
|
** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead |
|
** of a signed 32-bit integer. |
|
** |
|
** ^Calling sqlite3_free() with a pointer previously returned |
|
** by sqlite3_malloc() or sqlite3_realloc() releases that memory so |
|
** that it might be reused. ^The sqlite3_free() routine is |
|
** a no-op if is called with a NULL pointer. Passing a NULL pointer |
|
** to sqlite3_free() is harmless. After being freed, memory |
|
** should neither be read nor written. Even reading previously freed |
|
** memory might result in a segmentation fault or other severe error. |
|
** Memory corruption, a segmentation fault, or other severe error |
|
** might result if sqlite3_free() is called with a non-NULL pointer that |
|
** was not obtained from sqlite3_malloc() or sqlite3_realloc(). |
|
** |
|
** ^The sqlite3_realloc(X,N) interface attempts to resize a |
|
** prior memory allocation X to be at least N bytes. |
|
** ^If the X parameter to sqlite3_realloc(X,N) |
|
** is a NULL pointer then its behavior is identical to calling |
|
** sqlite3_malloc(N). |
|
** ^If the N parameter to sqlite3_realloc(X,N) is zero or |
|
** negative then the behavior is exactly the same as calling |
|
** sqlite3_free(X). |
|
** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation |
|
** of at least N bytes in size or NULL if insufficient memory is available. |
|
** ^If M is the size of the prior allocation, then min(N,M) bytes |
|
** of the prior allocation are copied into the beginning of buffer returned |
|
** by sqlite3_realloc(X,N) and the prior allocation is freed. |
|
** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the |
|
** prior allocation is not freed. |
|
** |
|
** ^The sqlite3_realloc64(X,N) interfaces works the same as |
|
** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead |
|
** of a 32-bit signed integer. |
|
** |
|
** ^If X is a memory allocation previously obtained from sqlite3_malloc(), |
|
** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then |
|
** sqlite3_msize(X) returns the size of that memory allocation in bytes. |
|
** ^The value returned by sqlite3_msize(X) might be larger than the number |
|
** of bytes requested when X was allocated. ^If X is a NULL pointer then |
|
** sqlite3_msize(X) returns zero. If X points to something that is not |
|
** the beginning of memory allocation, or if it points to a formerly |
|
** valid memory allocation that has now been freed, then the behavior |
|
** of sqlite3_msize(X) is undefined and possibly harmful. |
|
** |
|
** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(), |
|
** sqlite3_malloc64(), and sqlite3_realloc64() |
|
** is always aligned to at least an 8 byte boundary, or to a |
|
** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time |
|
** option is used. |
|
** |
|
** In SQLite version 3.5.0 and 3.5.1, it was possible to define |
|
** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in |
|
** implementation of these routines to be omitted. That capability |
|
** is no longer provided. Only built-in memory allocators can be used. |
|
** |
|
** Prior to SQLite version 3.7.10, the Windows OS interface layer called |
|
** the system malloc() and free() directly when converting |
|
** filenames between the UTF-8 encoding used by SQLite |
|
** and whatever filename encoding is used by the particular Windows |
|
** installation. Memory allocation errors were detected, but |
|
** they were reported back as [SQLITE_CANTOPEN] or |
|
** [SQLITE_IOERR] rather than [SQLITE_NOMEM]. |
|
** |
|
** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()] |
|
** must be either NULL or else pointers obtained from a prior |
|
** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have |
|
** not yet been released. |
|
** |
|
** The application must not read or write any part of |
|
** a block of memory after it has been released using |
|
** [sqlite3_free()] or [sqlite3_realloc()]. |
|
*/ |
|
SQLITE_API void *sqlite3_malloc(int); |
|
SQLITE_API void *sqlite3_malloc64(sqlite3_uint64); |
|
SQLITE_API void *sqlite3_realloc(void*, int); |
|
SQLITE_API void *sqlite3_realloc64(void*, sqlite3_uint64); |
|
SQLITE_API void sqlite3_free(void*); |
|
SQLITE_API sqlite3_uint64 sqlite3_msize(void*); |
|
|
|
/* |
|
** CAPI3REF: Memory Allocator Statistics |
|
** |
|
** SQLite provides these two interfaces for reporting on the status |
|
** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()] |
|
** routines, which form the built-in memory allocation subsystem. |
|
** |
|
** ^The [sqlite3_memory_used()] routine returns the number of bytes |
|
** of memory currently outstanding (malloced but not freed). |
|
** ^The [sqlite3_memory_highwater()] routine returns the maximum |
|
** value of [sqlite3_memory_used()] since the high-water mark |
|
** was last reset. ^The values returned by [sqlite3_memory_used()] and |
|
** [sqlite3_memory_highwater()] include any overhead |
|
** added by SQLite in its implementation of [sqlite3_malloc()], |
|
** but not overhead added by the any underlying system library |
|
** routines that [sqlite3_malloc()] may call. |
|
** |
|
** ^The memory high-water mark is reset to the current value of |
|
** [sqlite3_memory_used()] if and only if the parameter to |
|
** [sqlite3_memory_highwater()] is true. ^The value returned |
|
** by [sqlite3_memory_highwater(1)] is the high-water mark |
|
** prior to the reset. |
|
*/ |
|
SQLITE_API sqlite3_int64 sqlite3_memory_used(void); |
|
SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag); |
|
|
|
/* |
|
** CAPI3REF: Pseudo-Random Number Generator |
|
** |
|
** SQLite contains a high-quality pseudo-random number generator (PRNG) used to |
|
** select random [ROWID | ROWIDs] when inserting new records into a table that |
|
** already uses the largest possible [ROWID]. The PRNG is also used for |
|
** the build-in random() and randomblob() SQL functions. This interface allows |
|
** applications to access the same PRNG for other purposes. |
|
** |
|
** ^A call to this routine stores N bytes of randomness into buffer P. |
|
** ^The P parameter can be a NULL pointer. |
|
** |
|
** ^If this routine has not been previously called or if the previous |
|
** call had N less than one or a NULL pointer for P, then the PRNG is |
|
** seeded using randomness obtained from the xRandomness method of |
|
** the default [sqlite3_vfs] object. |
|
** ^If the previous call to this routine had an N of 1 or more and a |
|
** non-NULL P then the pseudo-randomness is generated |
|
** internally and without recourse to the [sqlite3_vfs] xRandomness |
|
** method. |
|
*/ |
|
SQLITE_API void sqlite3_randomness(int N, void *P); |
|
|
|
/* |
|
** CAPI3REF: Compile-Time Authorization Callbacks |
|
** METHOD: sqlite3 |
|
** |
|
** ^This routine registers an authorizer callback with a particular |
|
** [database connection], supplied in the first argument. |
|
** ^The authorizer callback is invoked as SQL statements are being compiled |
|
** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()], |
|
** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()]. ^At various |
|
** points during the compilation process, as logic is being created |
|
** to perform various actions, the authorizer callback is invoked to |
|
** see if those actions are allowed. ^The authorizer callback should |
|
** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the |
|
** specific action but allow the SQL statement to continue to be |
|
** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be |
|
** rejected with an error. ^If the authorizer callback returns |
|
** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY] |
|
** then the [sqlite3_prepare_v2()] or equivalent call that triggered |
|
** the authorizer will fail with an error message. |
|
** |
|
** When the callback returns [SQLITE_OK], that means the operation |
|
** requested is ok. ^When the callback returns [SQLITE_DENY], the |
|
** [sqlite3_prepare_v2()] or equivalent call that triggered the |
|
** authorizer will fail with an error message explaining that |
|
** access is denied. |
|
** |
|
** ^The first parameter to the authorizer callback is a copy of the third |
|
** parameter to the sqlite3_set_authorizer() interface. ^The second parameter |
|
** to the callback is an integer [SQLITE_COPY | action code] that specifies |
|
** the particular action to be authorized. ^The third through sixth parameters |
|
** to the callback are zero-terminated strings that contain additional |
|
** details about the action to be authorized. |
|
** |
|
** ^If the action code is [SQLITE_READ] |
|
** and the callback returns [SQLITE_IGNORE] then the |
|
** [prepared statement] statement is constructed to substitute |
|
** a NULL value in place of the table column that would have |
|
** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE] |
|
** return can be used to deny an untrusted user access to individual |
|
** columns of a table. |
|
** ^If the action code is [SQLITE_DELETE] and the callback returns |
|
** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the |
|
** [truncate optimization] is disabled and all rows are deleted individually. |
|
** |
|
** An authorizer is used when [sqlite3_prepare | preparing] |
|
** SQL statements from an untrusted source, to ensure that the SQL statements |
|
** do not try to access data they are not allowed to see, or that they do not |
|
** try to execute malicious statements that damage the database. For |
|
** example, an application may allow a user to enter arbitrary |
|
** SQL queries for evaluation by a database. But the application does |
|
** not want the user to be able to make arbitrary changes to the |
|
** database. An authorizer could then be put in place while the |
|
** user-entered SQL is being [sqlite3_prepare | prepared] that |
|
** disallows everything except [SELECT] statements. |
|
** |
|
** Applications that need to process SQL from untrusted sources |
|
** might also consider lowering resource limits using [sqlite3_limit()] |
|
** and limiting database size using the [max_page_count] [PRAGMA] |
|
** in addition to using an authorizer. |
|
** |
|
** ^(Only a single authorizer can be in place on a database connection |
|
** at a time. Each call to sqlite3_set_authorizer overrides the |
|
** previous call.)^ ^Disable the authorizer by installing a NULL callback. |
|
** The authorizer is disabled by default. |
|
** |
|
** The authorizer callback must not do anything that will modify |
|
** the database connection that invoked the authorizer callback. |
|
** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their |
|
** database connections for the meaning of "modify" in this paragraph. |
|
** |
|
** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the |
|
** statement might be re-prepared during [sqlite3_step()] due to a |
|
** schema change. Hence, the application should ensure that the |
|
** correct authorizer callback remains in place during the [sqlite3_step()]. |
|
** |
|
** ^Note that the authorizer callback is invoked only during |
|
** [sqlite3_prepare()] or its variants. Authorization is not |
|
** performed during statement evaluation in [sqlite3_step()], unless |
|
** as stated in the previous paragraph, sqlite3_step() invokes |
|
** sqlite3_prepare_v2() to reprepare a statement after a schema change. |
|
*/ |
|
SQLITE_API int sqlite3_set_authorizer( |
|
sqlite3*, |
|
int (*xAuth)(void*,int,const char*,const char*,const char*,const char*), |
|
void *pUserData |
|
); |
|
|
|
/* |
|
** CAPI3REF: Authorizer Return Codes |
|
** |
|
** The [sqlite3_set_authorizer | authorizer callback function] must |
|
** return either [SQLITE_OK] or one of these two constants in order |
|
** to signal SQLite whether or not the action is permitted. See the |
|
** [sqlite3_set_authorizer | authorizer documentation] for additional |
|
** information. |
|
** |
|
** Note that SQLITE_IGNORE is also used as a [conflict resolution mode] |
|
** returned from the [sqlite3_vtab_on_conflict()] interface. |
|
*/ |
|
#define SQLITE_DENY 1 /* Abort the SQL statement with an error */ |
|
#define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */ |
|
|
|
/* |
|
** CAPI3REF: Authorizer Action Codes |
|
** |
|
** The [sqlite3_set_authorizer()] interface registers a callback function |
|
** that is invoked to authorize certain SQL statement actions. The |
|
** second parameter to the callback is an integer code that specifies |
|
** what action is being authorized. These are the integer action codes that |
|
** the authorizer callback may be passed. |
|
** |
|
** These action code values signify what kind of operation is to be |
|
** authorized. The 3rd and 4th parameters to the authorization |
|
** callback function will be parameters or NULL depending on which of these |
|
** codes is used as the second parameter. ^(The 5th parameter to the |
|
** authorizer callback is the name of the database ("main", "temp", |
|
** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback |
|
** is the name of the inner-most trigger or view that is responsible for |
|
** the access attempt or NULL if this access attempt is directly from |
|
** top-level SQL code. |
|
*/ |
|
/******************************************* 3rd ************ 4th ***********/ |
|
#define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */ |
|
#define SQLITE_CREATE_TABLE 2 /* Table Name NULL */ |
|
#define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */ |
|
#define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */ |
|
#define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */ |
|
#define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */ |
|
#define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */ |
|
#define SQLITE_CREATE_VIEW 8 /* View Name NULL */ |
|
#define SQLITE_DELETE 9 /* Table Name NULL */ |
|
#define SQLITE_DROP_INDEX 10 /* Index Name Table Name */ |
|
#define SQLITE_DROP_TABLE 11 /* Table Name NULL */ |
|
#define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */ |
|
#define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */ |
|
#define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */ |
|
#define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */ |
|
#define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */ |
|
#define SQLITE_DROP_VIEW 17 /* View Name NULL */ |
|
#define SQLITE_INSERT 18 /* Table Name NULL */ |
|
#define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */ |
|
#define SQLITE_READ 20 /* Table Name Column Name */ |
|
#define SQLITE_SELECT 21 /* NULL NULL */ |
|
#define SQLITE_TRANSACTION 22 /* Operation NULL */ |
|
#define SQLITE_UPDATE 23 /* Table Name Column Name */ |
|
#define SQLITE_ATTACH 24 /* Filename NULL */ |
|
#define SQLITE_DETACH 25 /* Database Name NULL */ |
|
#define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */ |
|
#define SQLITE_REINDEX 27 /* Index Name NULL */ |
|
#define SQLITE_ANALYZE 28 /* Table Name NULL */ |
|
#define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */ |
|
#define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */ |
|
#define SQLITE_FUNCTION 31 /* NULL Function Name */ |
|
#define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */ |
|
#define SQLITE_COPY 0 /* No longer used */ |
|
#define SQLITE_RECURSIVE 33 /* NULL NULL */ |
|
|
|
/* |
|
** CAPI3REF: Tracing And Profiling Functions |
|
** METHOD: sqlite3 |
|
** |
|
** These routines are deprecated. Use the [sqlite3_trace_v2()] interface |
|
** instead of the routines described here. |
|
** |
|
** These routines register callback functions that can be used for |
|
** tracing and profiling the execution of SQL statements. |
|
** |
|
** ^The callback function registered by sqlite3_trace() is invoked at |
|
** various times when an SQL statement is being run by [sqlite3_step()]. |
|
** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the |
|
** SQL statement text as the statement first begins executing. |
|
** ^(Additional sqlite3_trace() callbacks might occur |
|
** as each triggered subprogram is entered. The callbacks for triggers |
|
** contain a UTF-8 SQL comment that identifies the trigger.)^ |
|
** |
|
** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit |
|
** the length of [bound parameter] expansion in the output of sqlite3_trace(). |
|
** |
|
** ^The callback function registered by sqlite3_profile() is invoked |
|
** as each SQL statement finishes. ^The profile callback contains |
|
** the original statement text and an estimate of wall-clock time |
|
** of how long that statement took to run. ^The profile callback |
|
** time is in units of nanoseconds, however the current implementation |
|
** is only capable of millisecond resolution so the six least significant |
|
** digits in the time are meaningless. Future versions of SQLite |
|
** might provide greater resolution on the profiler callback. The |
|
** sqlite3_profile() function is considered experimental and is |
|
** subject to change in future versions of SQLite. |
|
*/ |
|
SQLITE_API SQLITE_DEPRECATED void *sqlite3_trace(sqlite3*, |
|
void(*xTrace)(void*,const char*), void*); |
|
SQLITE_API SQLITE_DEPRECATED void *sqlite3_profile(sqlite3*, |
|
void(*xProfile)(void*,const char*,sqlite3_uint64), void*); |
|
|
|
/* |
|
** CAPI3REF: SQL Trace Event Codes |
|
** KEYWORDS: SQLITE_TRACE |
|
** |
|
** These constants identify classes of events that can be monitored |
|
** using the [sqlite3_trace_v2()] tracing logic. The third argument |
|
** to [sqlite3_trace_v2()] is an OR-ed combination of one or more of |
|
** the following constants. ^The first argument to the trace callback |
|
** is one of the following constants. |
|
** |
|
** New tracing constants may be added in future releases. |
|
** |
|
** ^A trace callback has four arguments: xCallback(T,C,P,X). |
|
** ^The T argument is one of the integer type codes above. |
|
** ^The C argument is a copy of the context pointer passed in as the |
|
** fourth argument to [sqlite3_trace_v2()]. |
|
** The P and X arguments are pointers whose meanings depend on T. |
|
** |
|
** <dl> |
|
** [[SQLITE_TRACE_STMT]] <dt>SQLITE_TRACE_STMT</dt> |
|
** <dd>^An SQLITE_TRACE_STMT callback is invoked when a prepared statement |
|
** first begins running and possibly at other times during the |
|
** execution of the prepared statement, such as at the start of each |
|
** trigger subprogram. ^The P argument is a pointer to the |
|
** [prepared statement]. ^The X argument is a pointer to a string which |
|
** is the unexpanded SQL text of the prepared statement or an SQL comment |
|
** that indicates the invocation of a trigger. ^The callback can compute |
|
** the same text that would have been returned by the legacy [sqlite3_trace()] |
|
** interface by using the X argument when X begins with "--" and invoking |
|
** [sqlite3_expanded_sql(P)] otherwise. |
|
** |
|
** [[SQLITE_TRACE_PROFILE]] <dt>SQLITE_TRACE_PROFILE</dt> |
|
** <dd>^An SQLITE_TRACE_PROFILE callback provides approximately the same |
|
** information as is provided by the [sqlite3_profile()] callback. |
|
** ^The P argument is a pointer to the [prepared statement] and the |
|
** X argument points to a 64-bit integer which is the estimated of |
|
** the number of nanosecond that the prepared statement took to run. |
|
** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes. |
|
** |
|
** [[SQLITE_TRACE_ROW]] <dt>SQLITE_TRACE_ROW</dt> |
|
** <dd>^An SQLITE_TRACE_ROW callback is invoked whenever a prepared |
|
** statement generates a single row of result. |
|
** ^The P argument is a pointer to the [prepared statement] and the |
|
** X argument is unused. |
|
** |
|
** [[SQLITE_TRACE_CLOSE]] <dt>SQLITE_TRACE_CLOSE</dt> |
|
** <dd>^An SQLITE_TRACE_CLOSE callback is invoked when a database |
|
** connection closes. |
|
** ^The P argument is a pointer to the [database connection] object |
|
** and the X argument is unused. |
|
** </dl> |
|
*/ |
|
#define SQLITE_TRACE_STMT 0x01 |
|
#define SQLITE_TRACE_PROFILE 0x02 |
|
#define SQLITE_TRACE_ROW 0x04 |
|
#define SQLITE_TRACE_CLOSE 0x08 |
|
|
|
/* |
|
** CAPI3REF: SQL Trace Hook |
|
** METHOD: sqlite3 |
|
** |
|
** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback |
|
** function X against [database connection] D, using property mask M |
|
** and context pointer P. ^If the X callback is |
|
** NULL or if the M mask is zero, then tracing is disabled. The |
|
** M argument should be the bitwise OR-ed combination of |
|
** zero or more [SQLITE_TRACE] constants. |
|
** |
|
** ^Each call to either sqlite3_trace() or sqlite3_trace_v2() overrides |
|
** (cancels) any prior calls to sqlite3_trace() or sqlite3_trace_v2(). |
|
** |
|
** ^The X callback is invoked whenever any of the events identified by |
|
** mask M occur. ^The integer return value from the callback is currently |
|
** ignored, though this may change in future releases. Callback |
|
** implementations should return zero to ensure future compatibility. |
|
** |
|
** ^A trace callback is invoked with four arguments: callback(T,C,P,X). |
|
** ^The T argument is one of the [SQLITE_TRACE] |
|
** constants to indicate why the callback was invoked. |
|
** ^The C argument is a copy of the context pointer. |
|
** The P and X arguments are pointers whose meanings depend on T. |
|
** |
|
** The sqlite3_trace_v2() interface is intended to replace the legacy |
|
** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which |
|
** are deprecated. |
|
*/ |
|
SQLITE_API int sqlite3_trace_v2( |
|
sqlite3*, |
|
unsigned uMask, |
|
int(*xCallback)(unsigned,void*,void*,void*), |
|
void *pCtx |
|
); |
|
|
|
/* |
|
** CAPI3REF: Query Progress Callbacks |
|
** METHOD: sqlite3 |
|
** |
|
** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback |
|
** function X to be invoked periodically during long running calls to |
|
** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for |
|
** database connection D. An example use for this |
|
** interface is to keep a GUI updated during a large query. |
|
** |
|
** ^The parameter P is passed through as the only parameter to the |
|
** callback function X. ^The parameter N is the approximate number of |
|
** [virtual machine instructions] that are evaluated between successive |
|
** invocations of the callback X. ^If N is less than one then the progress |
|
** handler is disabled. |
|
** |
|
** ^Only a single progress handler may be defined at one time per |
|
** [database connection]; setting a new progress handler cancels the |
|
** old one. ^Setting parameter X to NULL disables the progress handler. |
|
** ^The progress handler is also disabled by setting N to a value less |
|
** than 1. |
|
** |
|
** ^If the progress callback returns non-zero, the operation is |
|
** interrupted. This feature can be used to implement a |
|
** "Cancel" button on a GUI progress dialog box. |
|
** |
|
** The progress handler callback must not do anything that will modify |
|
** the database connection that invoked the progress handler. |
|
** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their |
|
** database connections for the meaning of "modify" in this paragraph. |
|
** |
|
*/ |
|
SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*); |
|
|
|
/* |
|
** CAPI3REF: Opening A New Database Connection |
|
** CONSTRUCTOR: sqlite3 |
|
** |
|
** ^These routines open an SQLite database file as specified by the |
|
** filename argument. ^The filename argument is interpreted as UTF-8 for |
|
** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte |
|
** order for sqlite3_open16(). ^(A [database connection] handle is usually |
|
** returned in *ppDb, even if an error occurs. The only exception is that |
|
** if SQLite is unable to allocate memory to hold the [sqlite3] object, |
|
** a NULL will be written into *ppDb instead of a pointer to the [sqlite3] |
|
** object.)^ ^(If the database is opened (and/or created) successfully, then |
|
** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The |
|
** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain |
|
** an English language description of the error following a failure of any |
|
** of the sqlite3_open() routines. |
|
** |
|
** ^The default encoding will be UTF-8 for databases created using |
|
** sqlite3_open() or sqlite3_open_v2(). ^The default encoding for databases |
|
** created using sqlite3_open16() will be UTF-16 in the native byte order. |
|
** |
|
** Whether or not an error occurs when it is opened, resources |
|
** associated with the [database connection] handle should be released by |
|
** passing it to [sqlite3_close()] when it is no longer required. |
|
** |
|
** The sqlite3_open_v2() interface works like sqlite3_open() |
|
** except that it accepts two additional parameters for additional control |
|
** over the new database connection. ^(The flags parameter to |
|
** sqlite3_open_v2() can take one of |
|
** the following three values, optionally combined with the |
|
** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE], |
|
** [SQLITE_OPEN_PRIVATECACHE], and/or [SQLITE_OPEN_URI] flags:)^ |
|
** |
|
** <dl> |
|
** ^(<dt>[SQLITE_OPEN_READONLY]</dt> |
|
** <dd>The database is opened in read-only mode. If the database does not |
|
** already exist, an error is returned.</dd>)^ |
|
** |
|
** ^(<dt>[SQLITE_OPEN_READWRITE]</dt> |
|
** <dd>The database is opened for reading and writing if possible, or reading |
|
** only if the file is write protected by the operating system. In either |
|
** case the database must already exist, otherwise an error is returned.</dd>)^ |
|
** |
|
** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt> |
|
** <dd>The database is opened for reading and writing, and is created if |
|
** it does not already exist. This is the behavior that is always used for |
|
** sqlite3_open() and sqlite3_open16().</dd>)^ |
|
** </dl> |
|
** |
|
** If the 3rd parameter to sqlite3_open_v2() is not one of the |
|
** combinations shown above optionally combined with other |
|
** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits] |
|
** then the behavior is undefined. |
|
** |
|
** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection |
|
** opens in the multi-thread [threading mode] as long as the single-thread |
|
** mode has not been set at compile-time or start-time. ^If the |
|
** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens |
|
** in the serialized [threading mode] unless single-thread was |
|
** previously selected at compile-time or start-time. |
|
** ^The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be |
|
** eligible to use [shared cache mode], regardless of whether or not shared |
|
** cache is enabled using [sqlite3_enable_shared_cache()]. ^The |
|
** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not |
|
** participate in [shared cache mode] even if it is enabled. |
|
** |
|
** ^The fourth parameter to sqlite3_open_v2() is the name of the |
|
** [sqlite3_vfs] object that defines the operating system interface that |
|
** the new database connection should use. ^If the fourth parameter is |
|
** a NULL pointer then the default [sqlite3_vfs] object is used. |
|
** |
|
** ^If the filename is ":memory:", then a private, temporary in-memory database |
|
** is created for the connection. ^This in-memory database will vanish when |
|
** the database connection is closed. Future versions of SQLite might |
|
** make use of additional special filenames that begin with the ":" character. |
|
** It is recommended that when a database filename actually does begin with |
|
** a ":" character you should prefix the filename with a pathname such as |
|
** "./" to avoid ambiguity. |
|
** |
|
** ^If the filename is an empty string, then a private, temporary |
|
** on-disk database will be created. ^This private database will be |
|
** automatically deleted as soon as the database connection is closed. |
|
** |
|
** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3> |
|
** |
|
** ^If [URI filename] interpretation is enabled, and the filename argument |
|
** begins with "file:", then the filename is interpreted as a URI. ^URI |
|
** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is |
|
** set in the fourth argument to sqlite3_open_v2(), or if it has |
|
** been enabled globally using the [SQLITE_CONFIG_URI] option with the |
|
** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option. |
|
** As of SQLite version 3.7.7, URI filename interpretation is turned off |
|
** by default, but future releases of SQLite might enable URI filename |
|
** interpretation by default. See "[URI filenames]" for additional |
|
** information. |
|
** |
|
** URI filenames are parsed according to RFC 3986. ^If the URI contains an |
|
** authority, then it must be either an empty string or the string |
|
** "localhost". ^If the authority is not an empty string or "localhost", an |
|
** error is returned to the caller. ^The fragment component of a URI, if |
|
** present, is ignored. |
|
** |
|
** ^SQLite uses the path component of the URI as the name of the disk file |
|
** which contains the database. ^If the path begins with a '/' character, |
|
** then it is interpreted as an absolute path. ^If the path does not begin |
|
** with a '/' (meaning that the authority section is omitted from the URI) |
|
** then the path is interpreted as a relative path. |
|
** ^(On windows, the first component of an absolute path |
|
** is a drive specification (e.g. "C:").)^ |
|
** |
|
** [[core URI query parameters]] |
|
** The query component of a URI may contain parameters that are interpreted |
|
** either by SQLite itself, or by a [VFS | custom VFS implementation]. |
|
** SQLite and its built-in [VFSes] interpret the |
|
** following query parameters: |
|
** |
|
** <ul> |
|
** <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of |
|
** a VFS object that provides the operating system interface that should |
|
** be used to access the database file on disk. ^If this option is set to |
|
** an empty string the default VFS object is used. ^Specifying an unknown |
|
** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is |
|
** present, then the VFS specified by the option takes precedence over |
|
** the value passed as the fourth parameter to sqlite3_open_v2(). |
|
** |
|
** <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw", |
|
** "rwc", or "memory". Attempting to set it to any other value is |
|
** an error)^. |
|
** ^If "ro" is specified, then the database is opened for read-only |
|
** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the |
|
** third argument to sqlite3_open_v2(). ^If the mode option is set to |
|
** "rw", then the database is opened for read-write (but not create) |
|
** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had |
|
** been set. ^Value "rwc" is equivalent to setting both |
|
** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If the mode option is |
|
** set to "memory" then a pure [in-memory database] that never reads |
|
** or writes from disk is used. ^It is an error to specify a value for |
|
** the mode parameter that is less restrictive than that specified by |
|
** the flags passed in the third parameter to sqlite3_open_v2(). |
|
** |
|
** <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or |
|
** "private". ^Setting it to "shared" is equivalent to setting the |
|
** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to |
|
** sqlite3_open_v2(). ^Setting the cache parameter to "private" is |
|
** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit. |
|
** ^If sqlite3_open_v2() is used and the "cache" parameter is present in |
|
** a URI filename, its value overrides any behavior requested by setting |
|
** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag. |
|
** |
|
** <li> <b>psow</b>: ^The psow parameter indicates whether or not the |
|
** [powersafe overwrite] property does or does not apply to the |
|
** storage media on which the database file resides. |
|
** |
|
** <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter |
|
** which if set disables file locking in rollback journal modes. This |
|
** is useful for accessing a database on a filesystem that does not |
|
** support locking. Caution: Database corruption might result if two |
|
** or more processes write to the same database and any one of those |
|
** processes uses nolock=1. |
|
** |
|
** <li> <b>immutable</b>: ^The immutable parameter is a boolean query |
|
** parameter that indicates that the database file is stored on |
|
** read-only media. ^When immutable is set, SQLite assumes that the |
|
** database file cannot be changed, even by a process with higher |
|
** privilege, and so the database is opened read-only and all locking |
|
** and change detection is disabled. Caution: Setting the immutable |
|
** property on a database file that does in fact change can result |
|
** in incorrect query results and/or [SQLITE_CORRUPT] errors. |
|
** See also: [SQLITE_IOCAP_IMMUTABLE]. |
|
** |
|
** </ul> |
|
** |
|
** ^Specifying an unknown parameter in the query component of a URI is not an |
|
** error. Future versions of SQLite might understand additional query |
|
** parameters. See "[query parameters with special meaning to SQLite]" for |
|
** additional information. |
|
** |
|
** [[URI filename examples]] <h3>URI filename examples</h3> |
|
** |
|
** <table border="1" align=center cellpadding=5> |
|
** <tr><th> URI filenames <th> Results |
|
** <tr><td> file:data.db <td> |
|
** Open the file "data.db" in the current directory. |
|
** <tr><td> file:/home/fred/data.db<br> |
|
** file:///home/fred/data.db <br> |
|
** file://localhost/home/fred/data.db <br> <td> |
|
** Open the database file "/home/fred/data.db". |
|
** <tr><td> file://darkstar/home/fred/data.db <td> |
|
** An error. "darkstar" is not a recognized authority. |
|
** <tr><td style="white-space:nowrap"> |
|
** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db |
|
** <td> Windows only: Open the file "data.db" on fred's desktop on drive |
|
** C:. Note that the %20 escaping in this example is not strictly |
|
** necessary - space characters can be used literally |
|
** in URI filenames. |
|
** <tr><td> file:data.db?mode=ro&cache=private <td> |
|
** Open file "data.db" in the current directory for read-only access. |
|
** Regardless of whether or not shared-cache mode is enabled by |
|
** default, use a private cache. |
|
** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td> |
|
** Open file "/home/fred/data.db". Use the special VFS "unix-dotfile" |
|
** that uses dot-files in place of posix advisory locking. |
|
** <tr><td> file:data.db?mode=readonly <td> |
|
** An error. "readonly" is not a valid option for the "mode" parameter. |
|
** </table> |
|
** |
|
** ^URI hexadecimal escape sequences (%HH) are supported within the path and |
|
** query components of a URI. A hexadecimal escape sequence consists of a |
|
** percent sign - "%" - followed by exactly two hexadecimal digits |
|
** specifying an octet value. ^Before the path or query components of a |
|
** URI filename are interpreted, they are encoded using UTF-8 and all |
|
** hexadecimal escape sequences replaced by a single byte containing the |
|
** corresponding octet. If this process generates an invalid UTF-8 encoding, |
|
** the results are undefined. |
|
** |
|
** <b>Note to Windows users:</b> The encoding used for the filename argument |
|
** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever |
|
** codepage is currently defined. Filenames containing international |
|
** characters must be converted to UTF-8 prior to passing them into |
|
** sqlite3_open() or sqlite3_open_v2(). |
|
** |
|
** <b>Note to Windows Runtime users:</b> The temporary directory must be set |
|
** prior to calling sqlite3_open() or sqlite3_open_v2(). Otherwise, various |
|
** features that require the use of temporary files may fail. |
|
** |
|
** See also: [sqlite3_temp_directory] |
|
*/ |
|
SQLITE_API int sqlite3_open( |
|
const char *filename, /* Database filename (UTF-8) */ |
|
sqlite3 **ppDb /* OUT: SQLite db handle */ |
|
); |
|
SQLITE_API int sqlite3_open16( |
|
const void *filename, /* Database filename (UTF-16) */ |
|
sqlite3 **ppDb /* OUT: SQLite db handle */ |
|
); |
|
SQLITE_API int sqlite3_open_v2( |
|
const char *filename, /* Database filename (UTF-8) */ |
|
sqlite3 **ppDb, /* OUT: SQLite db handle */ |
|
int flags, /* Flags */ |
|
const char *zVfs /* Name of VFS module to use */ |
|
); |
|
|
|
/* |
|
** CAPI3REF: Obtain Values For URI Parameters |
|
** |
|
** These are utility routines, useful to VFS implementations, that check |
|
** to see if a database file was a URI that contained a specific query |
|
** parameter, and if so obtains the value of that query parameter. |
|
** |
|
** If F is the database filename pointer passed into the xOpen() method of |
|
** a VFS implementation when the flags parameter to xOpen() has one or |
|
** more of the [SQLITE_OPEN_URI] or [SQLITE_OPEN_MAIN_DB] bits set and |
|
** P is the name of the query parameter, then |
|
** sqlite3_uri_parameter(F,P) returns the value of the P |
|
** parameter if it exists or a NULL pointer if P does not appear as a |
|
** query parameter on F. If P is a query parameter of F |
|
** has no explicit value, then sqlite3_uri_parameter(F,P) returns |
|
** a pointer to an empty string. |
|
** |
|
** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean |
|
** parameter and returns true (1) or false (0) according to the value |
|
** of P. The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the |
|
** value of query parameter P is one of "yes", "true", or "on" in any |
|
** case or if the value begins with a non-zero number. The |
|
** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of |
|
** query parameter P is one of "no", "false", or "off" in any case or |
|
** if the value begins with a numeric zero. If P is not a query |
|
** parameter on F or if the value of P is does not match any of the |
|
** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0). |
|
** |
|
** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a |
|
** 64-bit signed integer and returns that integer, or D if P does not |
|
** exist. If the value of P is something other than an integer, then |
|
** zero is returned. |
|
** |
|
** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and |
|
** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and |
|
** is not a database file pathname pointer that SQLite passed into the xOpen |
|
** VFS method, then the behavior of this routine is undefined and probably |
|
** undesirable. |
|
*/ |
|
SQLITE_API const char *sqlite3_uri_parameter(const char *zFilename, const char *zParam); |
|
SQLITE_API int sqlite3_uri_boolean(const char *zFile, const char *zParam, int bDefault); |
|
SQLITE_API sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int64); |
|
|
|
|
|
/* |
|
** CAPI3REF: Error Codes And Messages |
|
** METHOD: sqlite3 |
|
** |
|
** ^If the most recent sqlite3_* API call associated with |
|
** [database connection] D failed, then the sqlite3_errcode(D) interface |
|
** returns the numeric [result code] or [extended result code] for that |
|
** API call. |
|
** If the most recent API call was successful, |
|
** then the return value from sqlite3_errcode() is undefined. |
|
** ^The sqlite3_extended_errcode() |
|
** interface is the same except that it always returns the |
|
** [extended result code] even when extended result codes are |
|
** disabled. |
|
** |
|
** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language |
|
** text that describes the error, as either UTF-8 or UTF-16 respectively. |
|
** ^(Memory to hold the error message string is managed internally. |
|
** The application does not need to worry about freeing the result. |
|
** However, the error string might be overwritten or deallocated by |
|
** subsequent calls to other SQLite interface functions.)^ |
|
** |
|
** ^The sqlite3_errstr() interface returns the English-language text |
|
** that describes the [result code], as UTF-8. |
|
** ^(Memory to hold the error message string is managed internally |
|
** and must not be freed by the application)^. |
|
** |
|
** When the serialized [threading mode] is in use, it might be the |
|
** case that a second error occurs on a separate thread in between |
|
** the time of the first error and the call to these interfaces. |
|
** When that happens, the second error will be reported since these |
|
** interfaces always report the most recent result. To avoid |
|
** this, each thread can obtain exclusive use of the [database connection] D |
|
** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning |
|
** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after |
|
** all calls to the interfaces listed here are completed. |
|
** |
|
** If an interface fails with SQLITE_MISUSE, that means the interface |
|
** was invoked incorrectly by the application. In that case, the |
|
** error code and message may or may not be set. |
|
*/ |
|
SQLITE_API int sqlite3_errcode(sqlite3 *db); |
|
SQLITE_API int sqlite3_extended_errcode(sqlite3 *db); |
|
SQLITE_API const char *sqlite3_errmsg(sqlite3*); |
|
SQLITE_API const void *sqlite3_errmsg16(sqlite3*); |
|
SQLITE_API const char *sqlite3_errstr(int); |
|
|
|
/* |
|
** CAPI3REF: Prepared Statement Object |
|
** KEYWORDS: {prepared statement} {prepared statements} |
|
** |
|
** An instance of this object represents a single SQL statement that |
|
** has been compiled into binary form and is ready to be evaluated. |
|
** |
|
** Think of each SQL statement as a separate computer program. The |
|
** original SQL text is source code. A prepared statement object |
|
** is the compiled object code. All SQL must be converted into a |
|
** prepared statement before it can be run. |
|
** |
|
** The life-cycle of a prepared statement object usually goes like this: |
|
** |
|
** <ol> |
|
** <li> Create the prepared statement object using [sqlite3_prepare_v2()]. |
|
** <li> Bind values to [parameters] using the sqlite3_bind_*() |
|
** interfaces. |
|
** <li> Run the SQL by calling [sqlite3_step()] one or more times. |
|
** <li> Reset the prepared statement using [sqlite3_reset()] then go back |
|
** to step 2. Do this zero or more times. |
|
** <li> Destroy the object using [sqlite3_finalize()]. |
|
** </ol> |
|
*/ |
|
typedef struct sqlite3_stmt sqlite3_stmt; |
|
|
|
/* |
|
** CAPI3REF: Run-time Limits |
|
** METHOD: sqlite3 |
|
** |
|
** ^(This interface allows the size of various constructs to be limited |
|
** on a connection by connection basis. The first parameter is the |
|
** [database connection] whose limit is to be set or queried. The |
|
** second parameter is one of the [limit categories] that define a |
|
** class of constructs to be size limited. The third parameter is the |
|
** new limit for that construct.)^ |
|
** |
|
** ^If the new limit is a negative number, the limit is unchanged. |
|
** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a |
|
** [limits | hard upper bound] |
|
** set at compile-time by a C preprocessor macro called |
|
** [limits | SQLITE_MAX_<i>NAME</i>]. |
|
** (The "_LIMIT_" in the name is changed to "_MAX_".))^ |
|
** ^Attempts to increase a limit above its hard upper bound are |
|
** silently truncated to the hard upper bound. |
|
** |
|
** ^Regardless of whether or not the limit was changed, the |
|
** [sqlite3_limit()] interface returns the prior value of the limit. |
|
** ^Hence, to find the current value of a limit without changing it, |
|
** simply invoke this interface with the third parameter set to -1. |
|
** |
|
** Run-time limits are intended for use in applications that manage |
|
** both their own internal database and also databases that are controlled |
|
** by untrusted external sources. An example application might be a |
|
** web browser that has its own databases for storing history and |
|
** separate databases controlled by JavaScript applications downloaded |
|
** off the Internet. The internal databases can be given the |
|
** large, default limits. Databases managed by external sources can |
|
** be given much smaller limits designed to prevent a denial of service |
|
** attack. Developers might also want to use the [sqlite3_set_authorizer()] |
|
** interface to further control untrusted SQL. The size of the database |
|
** created by an untrusted script can be contained using the |
|
** [max_page_count] [PRAGMA]. |
|
** |
|
** New run-time limit categories may be added in future releases. |
|
*/ |
|
SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal); |
|
|
|
/* |
|
** CAPI3REF: Run-Time Limit Categories |
|
** KEYWORDS: {limit category} {*limit categories} |
|
** |
|
** These constants define various performance limits |
|
** that can be lowered at run-time using [sqlite3_limit()]. |
|
** The synopsis of the meanings of the various limits is shown below. |
|
** Additional information is available at [limits | Limits in SQLite]. |
|
** |
|
** <dl> |
|
** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt> |
|
** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^ |
|
** |
|
** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt> |
|
** <dd>The maximum length of an SQL statement, in bytes.</dd>)^ |
|
** |
|
** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt> |
|
** <dd>The maximum number of columns in a table definition or in the |
|
** result set of a [SELECT] or the maximum number of columns in an index |
|
** or in an ORDER BY or GROUP BY clause.</dd>)^ |
|
** |
|
** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt> |
|
** <dd>The maximum depth of the parse tree on any expression.</dd>)^ |
|
** |
|
** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt> |
|
** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^ |
|
** |
|
** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt> |
|
** <dd>The maximum number of instructions in a virtual machine program |
|
** used to implement an SQL statement. This limit is not currently |
|
** enforced, though that might be added in some future release of |
|
** SQLite.</dd>)^ |
|
** |
|
** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt> |
|
** <dd>The maximum number of arguments on a function.</dd>)^ |
|
** |
|
** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt> |
|
** <dd>The maximum number of [ATTACH | attached databases].)^</dd> |
|
** |
|
** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]] |
|
** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt> |
|
** <dd>The maximum length of the pattern argument to the [LIKE] or |
|
** [GLOB] operators.</dd>)^ |
|
** |
|
** [[SQLITE_LIMIT_VARIABLE_NUMBER]] |
|
** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt> |
|
** <dd>The maximum index number of any [parameter] in an SQL statement.)^ |
|
** |
|
** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt> |
|
** <dd>The maximum depth of recursion for triggers.</dd>)^ |
|
** |
|
** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt> |
|
** <dd>The maximum number of auxiliary worker threads that a single |
|
** [prepared statement] may start.</dd>)^ |
|
** </dl> |
|
*/ |
|
#define SQLITE_LIMIT_LENGTH 0 |
|
#define SQLITE_LIMIT_SQL_LENGTH 1 |
|
#define SQLITE_LIMIT_COLUMN 2 |
|
#define SQLITE_LIMIT_EXPR_DEPTH 3 |
|
#define SQLITE_LIMIT_COMPOUND_SELECT 4 |
|
#define SQLITE_LIMIT_VDBE_OP 5 |
|
#define SQLITE_LIMIT_FUNCTION_ARG 6 |
|
#define SQLITE_LIMIT_ATTACHED 7 |
|
#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8 |
|
#define SQLITE_LIMIT_VARIABLE_NUMBER 9 |
|
#define SQLITE_LIMIT_TRIGGER_DEPTH 10 |
|
#define SQLITE_LIMIT_WORKER_THREADS 11 |
|
|
|
/* |
|
** CAPI3REF: Compiling An SQL Statement |
|
** KEYWORDS: {SQL statement compiler} |
|
** METHOD: sqlite3 |
|
** CONSTRUCTOR: sqlite3_stmt |
|
** |
|
** To execute an SQL query, it must first be compiled into a byte-code |
|
** program using one of these routines. |
|
** |
|
** The first argument, "db", is a [database connection] obtained from a |
|
** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or |
|
** [sqlite3_open16()]. The database connection must not have been closed. |
|
** |
|
** The second argument, "zSql", is the statement to be compiled, encoded |
|
** as either UTF-8 or UTF-16. The sqlite3_prepare() and sqlite3_prepare_v2() |
|
** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2() |
|
** use UTF-16. |
|
** |
|
** ^If the nByte argument is negative, then zSql is read up to the |
|
** first zero terminator. ^If nByte is positive, then it is the |
|
** number of bytes read from zSql. ^If nByte is zero, then no prepared |
|
** statement is generated. |
|
** If the caller knows that the supplied string is nul-terminated, then |
|
** there is a small performance advantage to passing an nByte parameter that |
|
** is the number of bytes in the input string <i>including</i> |
|
** the nul-terminator. |
|
** |
|
** ^If pzTail is not NULL then *pzTail is made to point to the first byte |
|
** past the end of the first SQL statement in zSql. These routines only |
|
** compile the first statement in zSql, so *pzTail is left pointing to |
|
** what remains uncompiled. |
|
** |
|
** ^*ppStmt is left pointing to a compiled [prepared statement] that can be |
|
** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set |
|
** to NULL. ^If the input text contains no SQL (if the input is an empty |
|
** string or a comment) then *ppStmt is set to NULL. |
|
** The calling procedure is responsible for deleting the compiled |
|
** SQL statement using [sqlite3_finalize()] after it has finished with it. |
|
** ppStmt may not be NULL. |
|
** |
|
** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK]; |
|
** otherwise an [error code] is returned. |
|
** |
|
** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are |
|
** recommended for all new programs. The two older interfaces are retained |
|
** for backwards compatibility, but their use is discouraged. |
|
** ^In the "v2" interfaces, the prepared statement |
|
** that is returned (the [sqlite3_stmt] object) contains a copy of the |
|
** original SQL text. This causes the [sqlite3_step()] interface to |
|
** behave differently in three ways: |
|
** |
|
** <ol> |
|
** <li> |
|
** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it |
|
** always used to do, [sqlite3_step()] will automatically recompile the SQL |
|
** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY] |
|
** retries will occur before sqlite3_step() gives up and returns an error. |
|
** </li> |
|
** |
|
** <li> |
|
** ^When an error occurs, [sqlite3_step()] will return one of the detailed |
|
** [error codes] or [extended error codes]. ^The legacy behavior was that |
|
** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code |
|
** and the application would have to make a second call to [sqlite3_reset()] |
|
** in order to find the underlying cause of the problem. With the "v2" prepare |
|
** interfaces, the underlying reason for the error is returned immediately. |
|
** </li> |
|
** |
|
** <li> |
|
** ^If the specific value bound to [parameter | host parameter] in the |
|
** WHERE clause might influence the choice of query plan for a statement, |
|
** then the statement will be automatically recompiled, as if there had been |
|
** a schema change, on the first [sqlite3_step()] call following any change |
|
** to the [sqlite3_bind_text | bindings] of that [parameter]. |
|
** ^The specific value of WHERE-clause [parameter] might influence the |
|
** choice of query plan if the parameter is the left-hand side of a [LIKE] |
|
** or [GLOB] operator or if the parameter is compared to an indexed column |
|
** and the [SQLITE_ENABLE_STAT3] compile-time option is enabled. |
|
** </li> |
|
** </ol> |
|
*/ |
|
SQLITE_API int sqlite3_prepare( |
|
sqlite3 *db, /* Database handle */ |
|
const char *zSql, /* SQL statement, UTF-8 encoded */ |
|
int nByte, /* Maximum length of zSql in bytes. */ |
|
sqlite3_stmt **ppStmt, /* OUT: Statement handle */ |
|
const char **pzTail /* OUT: Pointer to unused portion of zSql */ |
|
); |
|
SQLITE_API int sqlite3_prepare_v2( |
|
sqlite3 *db, /* Database handle */ |
|
const char *zSql, /* SQL statement, UTF-8 encoded */ |
|
int nByte, /* Maximum length of zSql in bytes. */ |
|
sqlite3_stmt **ppStmt, /* OUT: Statement handle */ |
|
const char **pzTail /* OUT: Pointer to unused portion of zSql */ |
|
); |
|
SQLITE_API int sqlite3_prepare16( |
|
sqlite3 *db, /* Database handle */ |
|
const void *zSql, /* SQL statement, UTF-16 encoded */ |
|
int nByte, /* Maximum length of zSql in bytes. */ |
|
sqlite3_stmt **ppStmt, /* OUT: Statement handle */ |
|
const void **pzTail /* OUT: Pointer to unused portion of zSql */ |
|
); |
|
SQLITE_API int sqlite3_prepare16_v2( |
|
sqlite3 *db, /* Database handle */ |
|
const void *zSql, /* SQL statement, UTF-16 encoded */ |
|
int nByte, /* Maximum length of zSql in bytes. */ |
|
sqlite3_stmt **ppStmt, /* OUT: Statement handle */ |
|
const void **pzTail /* OUT: Pointer to unused portion of zSql */ |
|
); |
|
|
|
/* |
|
** CAPI3REF: Retrieving Statement SQL |
|
** METHOD: sqlite3_stmt |
|
** |
|
** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8 |
|
** SQL text used to create [prepared statement] P if P was |
|
** created by either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()]. |
|
** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8 |
|
** string containing the SQL text of prepared statement P with |
|
** [bound parameters] expanded. |
|
** |
|
** ^(For example, if a prepared statement is created using the SQL |
|
** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345 |
|
** and parameter :xyz is unbound, then sqlite3_sql() will return |
|
** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql() |
|
** will return "SELECT 2345,NULL".)^ |
|
** |
|
** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory |
|
** is available to hold the result, or if the result would exceed the |
|
** the maximum string length determined by the [SQLITE_LIMIT_LENGTH]. |
|
** |
|
** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of |
|
** bound parameter expansions. ^The [SQLITE_OMIT_TRACE] compile-time |
|
** option causes sqlite3_expanded_sql() to always return NULL. |
|
** |
|
** ^The string returned by sqlite3_sql(P) is managed by SQLite and is |
|
** automatically freed when the prepared statement is finalized. |
|
** ^The string returned by sqlite3_expanded_sql(P), on the other hand, |
|
** is obtained from [sqlite3_malloc()] and must be free by the application |
|
** by passing it to [sqlite3_free()]. |
|
*/ |
|
SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt); |
|
SQLITE_API char *sqlite3_expanded_sql(sqlite3_stmt *pStmt); |
|
|
|
/* |
|
** CAPI3REF: Determine If An SQL Statement Writes The Database |
|
** METHOD: sqlite3_stmt |
|
** |
|
** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if |
|
** and only if the [prepared statement] X makes no direct changes to |
|
** the content of the database file. |
|
** |
|
** Note that [application-defined SQL functions] or |
|
** [virtual tables] might change the database indirectly as a side effect. |
|
** ^(For example, if an application defines a function "eval()" that |
|
** calls [sqlite3_exec()], then the following SQL statement would |
|
** change the database file through side-effects: |
|
** |
|
** <blockquote><pre> |
|
** SELECT eval('DELETE FROM t1') FROM t2; |
|
** </pre></blockquote> |
|
** |
|
** But because the [SELECT] statement does not change the database file |
|
** directly, sqlite3_stmt_readonly() would still return true.)^ |
|
** |
|
** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK], |
|
** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true, |
|
** since the statements themselves do not actually modify the database but |
|
** rather they control the timing of when other statements modify the |
|
** database. ^The [ATTACH] and [DETACH] statements also cause |
|
** sqlite3_stmt_readonly() to return true since, while those statements |
|
** change the configuration of a database connection, they do not make |
|
** changes to the content of the database files on disk. |
|
*/ |
|
SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt); |
|
|
|
/* |
|
** CAPI3REF: Determine If A Prepared Statement Has Been Reset |
|
** METHOD: sqlite3_stmt |
|
** |
|
** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the |
|
** [prepared statement] S has been stepped at least once using |
|
** [sqlite3_step(S)] but has neither run to completion (returned |
|
** [SQLITE_DONE] from [sqlite3_step(S)]) nor |
|
** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S) |
|
** interface returns false if S is a NULL pointer. If S is not a |
|
** NULL pointer and is not a pointer to a valid [prepared statement] |
|
** object, then the behavior is undefined and probably undesirable. |
|
** |
|
** This interface can be used in combination [sqlite3_next_stmt()] |
|
** to locate all prepared statements associated with a database |
|
** connection that are in need of being reset. This can be used, |
|
** for example, in diagnostic routines to search for prepared |
|
** statements that are holding a transaction open. |
|
*/ |
|
SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*); |
|
|
|
/* |
|
** CAPI3REF: Dynamically Typed Value Object |
|
** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value} |
|
** |
|
** SQLite uses the sqlite3_value object to represent all values |
|
** that can be stored in a database table. SQLite uses dynamic typing |
|
** for the values it stores. ^Values stored in sqlite3_value objects |
|
** can be integers, floating point values, strings, BLOBs, or NULL. |
|
** |
|
** An sqlite3_value object may be either "protected" or "unprotected". |
|
** Some interfaces require a protected sqlite3_value. Other interfaces |
|
** will accept either a protected or an unprotected sqlite3_value. |
|
** Every interface that accepts sqlite3_value arguments specifies |
|
** whether or not it requires a protected sqlite3_value. The |
|
** [sqlite3_value_dup()] interface can be used to construct a new |
|
** protected sqlite3_value from an unprotected sqlite3_value. |
|
** |
|
** The terms "protected" and "unprotected" refer to whether or not |
|
** a mutex is held. An internal mutex is held for a protected |
|
** sqlite3_value object but no mutex is held for an unprotected |
|
** sqlite3_value object. If SQLite is compiled to be single-threaded |
|
** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0) |
|
** or if SQLite is run in one of reduced mutex modes |
|
** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD] |
|
** then there is no distinction between protected and unprotected |
|
** sqlite3_value objects and they can be used interchangeably. However, |
|
** for maximum code portability it is recommended that applications |
|
** still make the distinction between protected and unprotected |
|
** sqlite3_value objects even when not strictly required. |
|
** |
|
** ^The sqlite3_value objects that are passed as parameters into the |
|
** implementation of [application-defined SQL functions] are protected. |
|
** ^The sqlite3_value object returned by |
|
** [sqlite3_column_value()] is unprotected. |
|
** Unprotected sqlite3_value objects may only be used with |
|
** [sqlite3_result_value()] and [sqlite3_bind_value()]. |
|
** The [sqlite3_value_blob | sqlite3_value_type()] family of |
|
** interfaces require protected sqlite3_value objects. |
|
*/ |
|
typedef struct Mem sqlite3_value; |
|
|
|
/* |
|
** CAPI3REF: SQL Function Context Object |
|
** |
|
** The context in which an SQL function executes is stored in an |
|
** sqlite3_context object. ^A pointer to an sqlite3_context object |
|
** is always first parameter to [application-defined SQL functions]. |
|
** The application-defined SQL function implementation will pass this |
|
** pointer through into calls to [sqlite3_result_int | sqlite3_result()], |
|
** [sqlite3_aggregate_context()], [sqlite3_user_data()], |
|
** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()], |
|
** and/or [sqlite3_set_auxdata()]. |
|
*/ |
|
typedef struct sqlite3_context sqlite3_context; |
|
|
|
/* |
|
** CAPI3REF: Binding Values To Prepared Statements |
|
** KEYWORDS: {host parameter} {host parameters} {host parameter name} |
|
** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding} |
|
** METHOD: sqlite3_stmt |
|
** |
|
** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants, |
|
** literals may be replaced by a [parameter] that matches one of following |
|
** templates: |
|
** |
|
** <ul> |
|
** <li> ? |
|
** <li> ?NNN |
|
** <li> :VVV |
|
** <li> @VVV |
|
** <li> $VVV |
|
** </ul> |
|
** |
|
** In the templates above, NNN represents an integer literal, |
|
** and VVV represents an alphanumeric identifier.)^ ^The values of these |
|
** parameters (also called "host parameter names" or "SQL parameters") |
|
** can be set using the sqlite3_bind_*() routines defined here. |
|
** |
|
** ^The first argument to the sqlite3_bind_*() routines is always |
|
** a pointer to the [sqlite3_stmt] object returned from |
|
** [sqlite3_prepare_v2()] or its variants. |
|
** |
|
** ^The second argument is the index of the SQL parameter to be set. |
|
** ^The leftmost SQL parameter has an index of 1. ^When the same named |
|
** SQL parameter is used more than once, second and subsequent |
|
** occurrences have the same index as the first occurrence. |
|
** ^The index for named parameters can be looked up using the |
|
** [sqlite3_bind_parameter_index()] API if desired. ^The index |
|
** for "?NNN" parameters is the value of NNN. |
|
** ^The NNN value must be between 1 and the [sqlite3_limit()] |
|
** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999). |
|
** |
|
** ^The third argument is the value to bind to the parameter. |
|
** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16() |
|
** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter |
|
** is ignored and the end result is the same as sqlite3_bind_null(). |
|
** |
|
** ^(In those routines that have a fourth argument, its value is the |
|
** number of bytes in the parameter. To be clear: the value is the |
|
** number of <u>bytes</u> in the value, not the number of characters.)^ |
|
** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16() |
|
** is negative, then the length of the string is |
|
** the number of bytes up to the first zero terminator. |
|
** If the fourth parameter to sqlite3_bind_blob() is negative, then |
|
** the behavior is undefined. |
|
** If a non-negative fourth parameter is provided to sqlite3_bind_text() |
|
** or sqlite3_bind_text16() or sqlite3_bind_text64() then |
|
** that parameter must be the byte offset |
|
** where the NUL terminator would occur assuming the string were NUL |
|
** terminated. If any NUL characters occur at byte offsets less than |
|
** the value of the fourth parameter then the resulting string value will |
|
** contain embedded NULs. The result of expressions involving strings |
|
** with embedded NULs is undefined. |
|
** |
|
** ^The fifth argument to the BLOB and string binding interfaces |
|
** is a destructor used to dispose of the BLOB or |
|
** string after SQLite has finished with it. ^The destructor is called |
|
** to dispose of the BLOB or string even if the call to bind API fails. |
|
** ^If the fifth argument is |
|
** the special value [SQLITE_STATIC], then SQLite assumes that the |
|
** information is in static, unmanaged space and does not need to be freed. |
|
** ^If the fifth argument has the value [SQLITE_TRANSIENT], then |
|
** SQLite makes its own private copy of the data immediately, before |
|
** the sqlite3_bind_*() routine returns. |
|
** |
|
** ^The sixth argument to sqlite3_bind_text64() must be one of |
|
** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE] |
|
** to specify the encoding of the text in the third parameter. If |
|
** the sixth argument to sqlite3_bind_text64() is not one of the |
|
** allowed values shown above, or if the text encoding is different |
|
** from the encoding specified by the sixth parameter, then the behavior |
|
** is undefined. |
|
** |
|
** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that |
|
** is filled with zeroes. ^A zeroblob uses a fixed amount of memory |
|
** (just an integer to hold its size) while it is being processed. |
|
** Zeroblobs are intended to serve as placeholders for BLOBs whose |
|
** content is later written using |
|
** [sqlite3_blob_open | incremental BLOB I/O] routines. |
|
** ^A negative value for the zeroblob results in a zero-length BLOB. |
|
** |
|
** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer |
|
** for the [prepared statement] or with a prepared statement for which |
|
** [sqlite3_step()] has been called more recently than [sqlite3_reset()], |
|
** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_() |
|
** routine is passed a [prepared statement] that has been finalized, the |
|
** result is undefined and probably harmful. |
|
** |
|
** ^Bindings are not cleared by the [sqlite3_reset()] routine. |
|
** ^Unbound parameters are interpreted as NULL. |
|
** |
|
** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an |
|
** [error code] if anything goes wrong. |
|
** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB |
|
** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or |
|
** [SQLITE_MAX_LENGTH]. |
|
** ^[SQLITE_RANGE] is returned if the parameter |
|
** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails. |
|
** |
|
** See also: [sqlite3_bind_parameter_count()], |
|
** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()]. |
|
*/ |
|
SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*)); |
|
SQLITE_API int sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64, |
|
void(*)(void*)); |
|
SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double); |
|
SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int); |
|
SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64); |
|
SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int); |
|
SQLITE_API int sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*)); |
|
SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*)); |
|
SQLITE_API int sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64, |
|
void(*)(void*), unsigned char encoding); |
|
SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*); |
|
SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n); |
|
SQLITE_API int sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64); |
|
|
|
/* |
|
** CAPI3REF: Number Of SQL Parameters |
|
** METHOD: sqlite3_stmt |
|
** |
|
** ^This routine can be used to find the number of [SQL parameters] |
|
** in a [prepared statement]. SQL parameters are tokens of the |
|
** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as |
|
** placeholders for values that are [sqlite3_bind_blob | bound] |
|
** to the parameters at a later time. |
|
** |
|
** ^(This routine actually returns the index of the largest (rightmost) |
|
** parameter. For all forms except ?NNN, this will correspond to the |
|
** number of unique parameters. If parameters of the ?NNN form are used, |
|
** there may be gaps in the list.)^ |
|
** |
|
** See also: [sqlite3_bind_blob|sqlite3_bind()], |
|
** [sqlite3_bind_parameter_name()], and |
|
** [sqlite3_bind_parameter_index()]. |
|
*/ |
|
SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*); |
|
|
|
/* |
|
** CAPI3REF: Name Of A Host Parameter |
|
** METHOD: sqlite3_stmt |
|
** |
|
** ^The sqlite3_bind_parameter_name(P,N) interface returns |
|
** the name of the N-th [SQL parameter] in the [prepared statement] P. |
|
** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA" |
|
** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA" |
|
** respectively. |
|
** In other words, the initial ":" or "$" or "@" or "?" |
|
** is included as part of the name.)^ |
|
** ^Parameters of the form "?" without a following integer have no name |
|
** and are referred to as "nameless" or "anonymous parameters". |
|
** |
|
** ^The first host parameter has an index of 1, not 0. |
|
** |
|
** ^If the value N is out of range or if the N-th parameter is |
|
** nameless, then NULL is returned. ^The returned string is |
|
** always in UTF-8 encoding even if the named parameter was |
|
** originally specified as UTF-16 in [sqlite3_prepare16()] or |
|
** [sqlite3_prepare16_v2()]. |
|
** |
|
** See also: [sqlite3_bind_blob|sqlite3_bind()], |
|
** [sqlite3_bind_parameter_count()], and |
|
** [sqlite3_bind_parameter_index()]. |
|
*/ |
|
SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int); |
|
|
|
/* |
|
** CAPI3REF: Index Of A Parameter With A Given Name |
|
** METHOD: sqlite3_stmt |
|
** |
|
** ^Return the index of an SQL parameter given its name. ^The |
|
** index value returned is suitable for use as the second |
|
** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero |
|
** is returned if no matching parameter is found. ^The parameter |
|
** name must be given in UTF-8 even if the original statement |
|
** was prepared from UTF-16 text using [sqlite3_prepare16_v2()]. |
|
** |
|
** See also: [sqlite3_bind_blob|sqlite3_bind()], |
|
** [sqlite3_bind_parameter_count()], and |
|
** [sqlite3_bind_parameter_name()]. |
|
*/ |
|
SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName); |
|
|
|
/* |
|
** CAPI3REF: Reset All Bindings On A Prepared Statement |
|
** METHOD: sqlite3_stmt |
|
** |
|
** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset |
|
** the [sqlite3_bind_blob | bindings] on a [prepared statement]. |
|
** ^Use this routine to reset all host parameters to NULL. |
|
*/ |
|
SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*); |
|
|
|
/* |
|
** CAPI3REF: Number Of Columns In A Result Set |
|
** METHOD: sqlite3_stmt |
|
** |
|
** ^Return the number of columns in the result set returned by the |
|
** [prepared statement]. ^This routine returns 0 if pStmt is an SQL |
|
** statement that does not return data (for example an [UPDATE]). |
|
** |
|
** See also: [sqlite3_data_count()] |
|
*/ |
|
SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt); |
|
|
|
/* |
|
** CAPI3REF: Column Names In A Result Set |
|
** METHOD: sqlite3_stmt |
|
** |
|
** ^These routines return the name assigned to a particular column |
|
** in the result set of a [SELECT] statement. ^The sqlite3_column_name() |
|
** interface returns a pointer to a zero-terminated UTF-8 string |
|
** and sqlite3_column_name16() returns a pointer to a zero-terminated |
|
** UTF-16 string. ^The first parameter is the [prepared statement] |
|
** that implements the [SELECT] statement. ^The second parameter is the |
|
** column number. ^The leftmost column is number 0. |
|
** |
|
** ^The returned string pointer is valid until either the [prepared statement] |
|
** is destroyed by [sqlite3_finalize()] or until the statement is automatically |
|
** reprepared by the first call to [sqlite3_step()] for a particular run |
|
** or until the next call to |
|
** sqlite3_column_name() or sqlite3_column_name16() on the same column. |
|
** |
|
** ^If sqlite3_malloc() fails during the processing of either routine |
|
** (for example during a conversion from UTF-8 to UTF-16) then a |
|
** NULL pointer is returned. |
|
** |
|
** ^The name of a result column is the value of the "AS" clause for |
|
** that column, if there is an AS clause. If there is no AS clause |
|
** then the name of the column is unspecified and may change from |
|
** one release of SQLite to the next. |
|
*/ |
|
SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N); |
|
SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N); |
|
|
|
/* |
|
** CAPI3REF: Source Of Data In A Query Result |
|
** METHOD: sqlite3_stmt |
|
** |
|
** ^These routines provide a means to determine the database, table, and |
|
** table column that is the origin of a particular result column in |
|
** [SELECT] statement. |
|
** ^The name of the database or table or column can be returned as |
|
** either a UTF-8 or UTF-16 string. ^The _database_ routines return |
|
** the database name, the _table_ routines return the table name, and |
|
** the origin_ routines return the column name. |
|
** ^The returned string is valid until the [prepared statement] is destroyed |
|
** using [sqlite3_finalize()] or until the statement is automatically |
|
** reprepared by the first call to [sqlite3_step()] for a particular run |
|
** or until the same information is requested |
|
** again in a different encoding. |
|
** |
|
** ^The names returned are the original un-aliased names of the |
|
** database, table, and column. |
|
** |
|
** ^The first argument to these interfaces is a [prepared statement]. |
|
** ^These functions return information about the Nth result column returned by |
|
** the statement, where N is the second function argument. |
|
** ^The left-most column is column 0 for these routines. |
|
** |
|
** ^If the Nth column returned by the statement is an expression or |
|
** subquery and is not a column value, then all of these functions return |
|
** NULL. ^These routine might also return NULL if a memory allocation error |
|
** occurs. ^Otherwise, they return the name of the attached database, table, |
|
** or column that query result column was extracted from. |
|
** |
|
** ^As with all other SQLite APIs, those whose names end with "16" return |
|
** UTF-16 encoded strings and the other functions return UTF-8. |
|
** |
|
** ^These APIs are only available if the library was compiled with the |
|
** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol. |
|
** |
|
** If two or more threads call one or more of these routines against the same |
|
** prepared statement and column at the same time then the results are |
|
** undefined. |
|
** |
|
** If two or more threads call one or more |
|
** [sqlite3_column_database_name | column metadata interfaces] |
|
** for the same [prepared statement] and result column |
|
** at the same time then the results are undefined. |
|
*/ |
|
SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int); |
|
SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int); |
|
SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int); |
|
SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int); |
|
SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int); |
|
SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int); |
|
|
|
/* |
|
** CAPI3REF: Declared Datatype Of A Query Result |
|
** METHOD: sqlite3_stmt |
|
** |
|
** ^(The first parameter is a [prepared statement]. |
|
** If this statement is a [SELECT] statement and the Nth column of the |
|
** returned result set of that [SELECT] is a table column (not an |
|
** expression or subquery) then the declared type of the table |
|
** column is returned.)^ ^If the Nth column of the result set is an |
|
** expression or subquery, then a NULL pointer is returned. |
|
** ^The returned string is always UTF-8 encoded. |
|
** |
|
** ^(For example, given the database schema: |
|
** |
|
** CREATE TABLE t1(c1 VARIANT); |
|
** |
|
** and the following statement to be compiled: |
|
** |
|
** SELECT c1 + 1, c1 FROM t1; |
|
** |
|
** this routine would return the string "VARIANT" for the second result |
|
** column (i==1), and a NULL pointer for the first result column (i==0).)^ |
|
** |
|
** ^SQLite uses dynamic run-time typing. ^So just because a column |
|
** is declared to contain a particular type does not mean that the |
|
** data stored in that column is of the declared type. SQLite is |
|
** strongly typed, but the typing is dynamic not static. ^Type |
|
** is associated with individual values, not with the containers |
|
** used to hold those values. |
|
*/ |
|
SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int); |
|
SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int); |
|
|
|
/* |
|
** CAPI3REF: Evaluate An SQL Statement |
|
** METHOD: sqlite3_stmt |
|
** |
|
** After a [prepared statement] has been prepared using either |
|
** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy |
|
** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function |
|
** must be called one or more times to evaluate the statement. |
|
** |
|
** The details of the behavior of the sqlite3_step() interface depend |
|
** on whether the statement was prepared using the newer "v2" interface |
|
** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy |
|
** interface [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the |
|
** new "v2" interface is recommended for new applications but the legacy |
|
** interface will continue to be supported. |
|
** |
|
** ^In the legacy interface, the return value will be either [SQLITE_BUSY], |
|
** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE]. |
|
** ^With the "v2" interface, any of the other [result codes] or |
|
** [extended result codes] might be returned as well. |
|
** |
|
** ^[SQLITE_BUSY] means that the database engine was unable to acquire the |
|
** database locks it needs to do its job. ^If the statement is a [COMMIT] |
|
** or occurs outside of an explicit transaction, then you can retry the |
|
** statement. If the statement is not a [COMMIT] and occurs within an |
|
** explicit transaction then you should rollback the transaction before |
|
** continuing. |
|
** |
|
** ^[SQLITE_DONE] means that the statement has finished executing |
|
** successfully. sqlite3_step() should not be called again on this virtual |
|
** machine without first calling [sqlite3_reset()] to reset the virtual |
|
** machine back to its initial state. |
|
** |
|
** ^If the SQL statement being executed returns any data, then [SQLITE_ROW] |
|
** is returned each time a new row of data is ready for processing by the |
|
** caller. The values may be accessed using the [column access functions]. |
|
** sqlite3_step() is called again to retrieve the next row of data. |
|
** |
|
** ^[SQLITE_ERROR] means that a run-time error (such as a constraint |
|
** violation) has occurred. sqlite3_step() should not be called again on |
|
** the VM. More information may be found by calling [sqlite3_errmsg()]. |
|
** ^With the legacy interface, a more specific error code (for example, |
|
** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth) |
|
** can be obtained by calling [sqlite3_reset()] on the |
|
** [prepared statement]. ^In the "v2" interface, |
|
** the more specific error code is returned directly by sqlite3_step(). |
|
** |
|
** [SQLITE_MISUSE] means that the this routine was called inappropriately. |
|
** Perhaps it was called on a [prepared statement] that has |
|
** already been [sqlite3_finalize | finalized] or on one that had |
|
** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could |
|
** be the case that the same database connection is being used by two or |
|
** more threads at the same moment in time. |
|
** |
|
** For all versions of SQLite up to and including 3.6.23.1, a call to |
|
** [sqlite3_reset()] was required after sqlite3_step() returned anything |
|
** other than [SQLITE_ROW] before any subsequent invocation of |
|
** sqlite3_step(). Failure to reset the prepared statement using |
|
** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from |
|
** sqlite3_step(). But after [version 3.6.23.1] ([dateof:3.6.23.1], |
|
** sqlite3_step() began |
|
** calling [sqlite3_reset()] automatically in this circumstance rather |
|
** than returning [SQLITE_MISUSE]. This is not considered a compatibility |
|
** break because any application that ever receives an SQLITE_MISUSE error |
|
** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option |
|
** can be used to restore the legacy behavior. |
|
** |
|
** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step() |
|
** API always returns a generic error code, [SQLITE_ERROR], following any |
|
** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call |
|
** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the |
|
** specific [error codes] that better describes the error. |
|
** We admit that this is a goofy design. The problem has been fixed |
|
** with the "v2" interface. If you prepare all of your SQL statements |
|
** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead |
|
** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces, |
|
** then the more specific [error codes] are returned directly |
|
** by sqlite3_step(). The use of the "v2" interface is recommended. |
|
*/ |
|
SQLITE_API int sqlite3_step(sqlite3_stmt*); |
|
|
|
/* |
|
** CAPI3REF: Number of columns in a result set |
|
** METHOD: sqlite3_stmt |
|
** |
|
** ^The sqlite3_data_count(P) interface returns the number of columns in the |
|
** current row of the result set of [prepared statement] P. |
|
** ^If prepared statement P does not have results ready to return |
|
** (via calls to the [sqlite3_column_int | sqlite3_column_*()] of |
|
** interfaces) then sqlite3_data_count(P) returns 0. |
|
** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer. |
|
** ^The sqlite3_data_count(P) routine returns 0 if the previous call to |
|
** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P) |
|
** will return non-zero if previous call to [sqlite3_step](P) returned |
|
** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum] |
|
** where it always returns zero since each step of that multi-step |
|
** pragma returns 0 columns of data. |
|
** |
|
** See also: [sqlite3_column_count()] |
|
*/ |
|
SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt); |
|
|
|
/* |
|
** CAPI3REF: Fundamental Datatypes |
|
** KEYWORDS: SQLITE_TEXT |
|
** |
|
** ^(Every value in SQLite has one of five fundamental datatypes: |
|
** |
|
** <ul> |
|
** <li> 64-bit signed integer |
|
** <li> 64-bit IEEE floating point number |
|
** <li> string |
|
** <li> BLOB |
|
** <li> NULL |
|
** </ul>)^ |
|
** |
|
** These constants are codes for each of those types. |
|
** |
|
** Note that the SQLITE_TEXT constant was also used in SQLite version 2 |
|
** for a completely different meaning. Software that links against both |
|
** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not |
|
** SQLITE_TEXT. |
|
*/ |
|
#define SQLITE_INTEGER 1 |
|
#define SQLITE_FLOAT 2 |
|
#define SQLITE_BLOB 4 |
|
#define SQLITE_NULL 5 |
|
#ifdef SQLITE_TEXT |
|
# undef SQLITE_TEXT |
|
#else |
|
# define SQLITE_TEXT 3 |
|
#endif |
|
#define SQLITE3_TEXT 3 |
|
|
|
/* |
|
** CAPI3REF: Result Values From A Query |
|
** KEYWORDS: {column access functions} |
|
** METHOD: sqlite3_stmt |
|
** |
|
** ^These routines return information about a single column of the current |
|
** result row of a query. ^In every case the first argument is a pointer |
|
** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*] |
|
** that was returned from [sqlite3_prepare_v2()] or one of its variants) |
|
** and the second argument is the index of the column for which information |
|
** should be returned. ^The leftmost column of the result set has the index 0. |
|
** ^The number of columns in the result can be determined using |
|
** [sqlite3_column_count()]. |
|
** |
|
** If the SQL statement does not currently point to a valid row, or if the |
|
** column index is out of range, the result is undefined. |
|
** These routines may only be called when the most recent call to |
|
** [sqlite3_step()] has returned [SQLITE_ROW] and neither |
|
** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently. |
|
** If any of these routines are called after [sqlite3_reset()] or |
|
** [sqlite3_finalize()] or after [sqlite3_step()] has returned |
|
** something other than [SQLITE_ROW], the results are undefined. |
|
** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()] |
|
** are called from a different thread while any of these routines |
|
** are pending, then the results are undefined. |
|
** |
|
** ^The sqlite3_column_type() routine returns the |
|
** [SQLITE_INTEGER | datatype code] for the initial data type |
|
** of the result column. ^The returned value is one of [SQLITE_INTEGER], |
|
** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. The value |
|
** returned by sqlite3_column_type() is only meaningful if no type |
|
** conversions have occurred as described below. After a type conversion, |
|
** the value returned by sqlite3_column_type() is undefined. Future |
|
** versions of SQLite may change the behavior of sqlite3_column_type() |
|
** following a type conversion. |
|
** |
|
** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes() |
|
** routine returns the number of bytes in that BLOB or string. |
|
** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts |
|
** the string to UTF-8 and then returns the number of bytes. |
|
** ^If the result is a numeric value then sqlite3_column_bytes() uses |
|
** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns |
|
** the number of bytes in that string. |
|
** ^If the result is NULL, then sqlite3_column_bytes() returns zero. |
|
** |
|
** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16() |
|
** routine returns the number of bytes in that BLOB or string. |
|
** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts |
|
** the string to UTF-16 and then returns the number of bytes. |
|
** ^If the result is a numeric value then sqlite3_column_bytes16() uses |
|
** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns |
|
** the number of bytes in that string. |
|
** ^If the result is NULL, then sqlite3_column_bytes16() returns zero. |
|
** |
|
** ^The values returned by [sqlite3_column_bytes()] and |
|
** [sqlite3_column_bytes16()] do not include the zero terminators at the end |
|
** of the string. ^For clarity: the values returned by |
|
** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of |
|
** bytes in the string, not the number of characters. |
|
** |
|
** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(), |
|
** even empty strings, are always zero-terminated. ^The return |
|
** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer. |
|
** |
|
** <b>Warning:</b> ^The object returned by [sqlite3_column_value()] is an |
|
** [unprotected sqlite3_value] object. In a multithreaded environment, |
|
** an unprotected sqlite3_value object may only be used safely with |
|
** [sqlite3_bind_value()] and [sqlite3_result_value()]. |
|
** If the [unprotected sqlite3_value] object returned by |
|
** [sqlite3_column_value()] is used in any other way, including calls |
|
** to routines like [sqlite3_value_int()], [sqlite3_value_text()], |
|
** or [sqlite3_value_bytes()], the behavior is not threadsafe. |
|
** |
|
** These routines attempt to convert the value where appropriate. ^For |
|
** example, if the internal representation is FLOAT and a text result |
|
** is requested, [sqlite3_snprintf()] is used internally to perform the |
|
** conversion automatically. ^(The following table details the conversions |
|
** that are applied: |
|
** |
|
** <blockquote> |
|
** <table border="1"> |
|
** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion |
|
** |
|
** <tr><td> NULL <td> INTEGER <td> Result is 0 |
|
** <tr><td> NULL <td> FLOAT <td> Result is 0.0 |
|
** <tr><td> NULL <td> TEXT <td> Result is a NULL pointer |
|
** <tr><td> NULL <td> BLOB <td> Result is a NULL pointer |
|
** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float |
|
** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer |
|
** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT |
|
** <tr><td> FLOAT <td> INTEGER <td> [CAST] to INTEGER |
|
** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float |
|
** <tr><td> FLOAT <td> BLOB <td> [CAST] to BLOB |
|
** <tr><td> TEXT <td> INTEGER <td> [CAST] to INTEGER |
|
** <tr><td> TEXT <td> FLOAT <td> [CAST] to REAL |
|
** <tr><td> TEXT <td> BLOB <td> No change |
|
** <tr><td> BLOB <td> INTEGER <td> [CAST] to INTEGER |
|
** <tr><td> BLOB <td> FLOAT <td> [CAST] to REAL |
|
** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed |
|
** </table> |
|
** </blockquote>)^ |
|
** |
|
** Note that when type conversions occur, pointers returned by prior |
|
** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or |
|
** sqlite3_column_text16() may be invalidated. |
|
** Type conversions and pointer invalidations might occur |
|
** in the following cases: |
|
** |
|
** <ul> |
|
** <li> The initial content is a BLOB and sqlite3_column_text() or |
|
** sqlite3_column_text16() is called. A zero-terminator might |
|
** need to be added to the string.</li> |
|
** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or |
|
** sqlite3_column_text16() is called. The content must be converted |
|
** to UTF-16.</li> |
|
** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or |
|
** sqlite3_column_text() is called. The content must be converted |
|
** to UTF-8.</li> |
|
** </ul> |
|
** |
|
** ^Conversions between UTF-16be and UTF-16le are always done in place and do |
|
** not invalidate a prior pointer, though of course the content of the buffer |
|
** that the prior pointer references will have been modified. Other kinds |
|
** of conversion are done in place when it is possible, but sometimes they |
|
** are not possible and in those cases prior pointers are invalidated. |
|
** |
|
** The safest policy is to invoke these routines |
|
** in one of the following ways: |
|
** |
|
** <ul> |
|
** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li> |
|
** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li> |
|
** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li> |
|
** </ul> |
|
** |
|
** In other words, you should call sqlite3_column_text(), |
|
** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result |
|
** into the desired format, then invoke sqlite3_column_bytes() or |
|
** sqlite3_column_bytes16() to find the size of the result. Do not mix calls |
|
** to sqlite3_column_text() or sqlite3_column_blob() with calls to |
|
** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16() |
|
** with calls to sqlite3_column_bytes(). |
|
** |
|
** ^The pointers returned are valid until a type conversion occurs as |
|
** described above, or until [sqlite3_step()] or [sqlite3_reset()] or |
|
** [sqlite3_finalize()] is called. ^The memory space used to hold strings |
|
** and BLOBs is freed automatically. Do <em>not</em> pass the pointers returned |
|
** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into |
|
** [sqlite3_free()]. |
|
** |
|
** ^(If a memory allocation error occurs during the evaluation of any |
|
** of these routines, a default value is returned. The default value |
|
** is either the integer 0, the floating point number 0.0, or a NULL |
|
** pointer. Subsequent calls to [sqlite3_errcode()] will return |
|
** [SQLITE_NOMEM].)^ |
|
*/ |
|
SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol); |
|
SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol); |
|
SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol); |
|
SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol); |
|
SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol); |
|
SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol); |
|
SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol); |
|
SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol); |
|
SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol); |
|
SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol); |
|
|
|
/* |
|
** CAPI3REF: Destroy A Prepared Statement Object |
|
** DESTRUCTOR: sqlite3_stmt |
|
** |
|
** ^The sqlite3_finalize() function is called to delete a [prepared statement]. |
|
** ^If the most recent evaluation of the statement encountered no errors |
|
** or if the statement is never been evaluated, then sqlite3_finalize() returns |
|
** SQLITE_OK. ^If the most recent evaluation of statement S failed, then |
|
** sqlite3_finalize(S) returns the appropriate [error code] or |
|
** [extended error code]. |
|
** |
|
** ^The sqlite3_finalize(S) routine can be called at any point during |
|
** the life cycle of [prepared statement] S: |
|
** before statement S is ever evaluated, after |
|
** one or more calls to [sqlite3_reset()], or after any call |
|
** to [sqlite3_step()] regardless of whether or not the statement has |
|
** completed execution. |
|
** |
|
** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op. |
|
** |
|
** The application must finalize every [prepared statement] in order to avoid |
|
** resource leaks. It is a grievous error for the application to try to use |
|
** a prepared statement after it has been finalized. Any use of a prepared |
|
** statement after it has been finalized can result in undefined and |
|
** undesirable behavior such as segfaults and heap corruption. |
|
*/ |
|
SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt); |
|
|
|
/* |
|
** CAPI3REF: Reset A Prepared Statement Object |
|
** METHOD: sqlite3_stmt |
|
** |
|
** The sqlite3_reset() function is called to reset a [prepared statement] |
|
** object back to its initial state, ready to be re-executed. |
|
** ^Any SQL statement variables that had values bound to them using |
|
** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values. |
|
** Use [sqlite3_clear_bindings()] to reset the bindings. |
|
** |
|
** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S |
|
** back to the beginning of its program. |
|
** |
|
** ^If the most recent call to [sqlite3_step(S)] for the |
|
** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE], |
|
** or if [sqlite3_step(S)] has never before been called on S, |
|
** then [sqlite3_reset(S)] returns [SQLITE_OK]. |
|
** |
|
** ^If the most recent call to [sqlite3_step(S)] for the |
|
** [prepared statement] S indicated an error, then |
|
** [sqlite3_reset(S)] returns an appropriate [error code]. |
|
** |
|
** ^The [sqlite3_reset(S)] interface does not change the values |
|
** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S. |
|
*/ |
|
SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt); |
|
|
|
/* |
|
** CAPI3REF: Create Or Redefine SQL Functions |
|
** KEYWORDS: {function creation routines} |
|
** KEYWORDS: {application-defined SQL function} |
|
** KEYWORDS: {application-defined SQL functions} |
|
** METHOD: sqlite3 |
|
** |
|
** ^These functions (collectively known as "function creation routines") |
|
** are used to add SQL functions or aggregates or to redefine the behavior |
|
** of existing SQL functions or aggregates. The only differences between |
|
** these routines are the text encoding expected for |
|
** the second parameter (the name of the function being created) |
|
** and the presence or absence of a destructor callback for |
|
** the application data pointer. |
|
** |
|
** ^The first parameter is the [database connection] to which the SQL |
|
** function is to be added. ^If an application uses more than one database |
|
** connection then application-defined SQL functions must be added |
|
** to each database connection separately. |
|
** |
|
** ^The second parameter is the name of the SQL function to be created or |
|
** redefined. ^The length of the name is limited to 255 bytes in a UTF-8 |
|
** representation, exclusive of the zero-terminator. ^Note that the name |
|
** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes. |
|
** ^Any attempt to create a function with a longer name |
|
** will result in [SQLITE_MISUSE] being returned. |
|
** |
|
** ^The third parameter (nArg) |
|
** is the number of arguments that the SQL function or |
|
** aggregate takes. ^If this parameter is -1, then the SQL function or |
|
** aggregate may take any number of arguments between 0 and the limit |
|
** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third |
|
** parameter is less than -1 or greater than 127 then the behavior is |
|
** undefined. |
|
** |
|
** ^The fourth parameter, eTextRep, specifies what |
|
** [SQLITE_UTF8 | text encoding] this SQL function prefers for |
|
** its parameters. The application should set this parameter to |
|
** [SQLITE_UTF16LE] if the function implementation invokes |
|
** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the |
|
** implementation invokes [sqlite3_value_text16be()] on an input, or |
|
** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8] |
|
** otherwise. ^The same SQL function may be registered multiple times using |
|
** different preferred text encodings, with different implementations for |
|
** each encoding. |
|
** ^When multiple implementations of the same function are available, SQLite |
|
** will pick the one that involves the least amount of data conversion. |
|
** |
|
** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC] |
|
** to signal that the function will always return the same result given |
|
** the same inputs within a single SQL statement. Most SQL functions are |
|
** deterministic. The built-in [random()] SQL function is an example of a |
|
** function that is not deterministic. The SQLite query planner is able to |
|
** perform additional optimizations on deterministic functions, so use |
|
** of the [SQLITE_DETERMINISTIC] flag is recommended where possible. |
|
** |
|
** ^(The fifth parameter is an arbitrary pointer. The implementation of the |
|
** function can gain access to this pointer using [sqlite3_user_data()].)^ |
|
** |
|
** ^The sixth, seventh and eighth parameters, xFunc, xStep and xFinal, are |
|
** pointers to C-language functions that implement the SQL function or |
|
** aggregate. ^A scalar SQL function requires an implementation of the xFunc |
|
** callback only; NULL pointers must be passed as the xStep and xFinal |
|
** parameters. ^An aggregate SQL function requires an implementation of xStep |
|
** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing |
|
** SQL function or aggregate, pass NULL pointers for all three function |
|
** callbacks. |
|
** |
|
** ^(If the ninth parameter to sqlite3_create_function_v2() is not NULL, |
|
** then it is destructor for the application data pointer. |
|
** The destructor is invoked when the function is deleted, either by being |
|
** overloaded or when the database connection closes.)^ |
|
** ^The destructor is also invoked if the call to |
|
** sqlite3_create_function_v2() fails. |
|
** ^When the destructor callback of the tenth parameter is invoked, it |
|
** is passed a single argument which is a copy of the application data |
|
** pointer which was the fifth parameter to sqlite3_create_function_v2(). |
|
** |
|
** ^It is permitted to register multiple implementations of the same |
|
** functions with the same name but with either differing numbers of |
|
** arguments or differing preferred text encodings. ^SQLite will use |
|
** the implementation that most closely matches the way in which the |
|
** SQL function is used. ^A function implementation with a non-negative |
|
** nArg parameter is a better match than a function implementation with |
|
** a negative nArg. ^A function where the preferred text encoding |
|
** matches the database encoding is a better |
|
** match than a function where the encoding is different. |
|
** ^A function where the encoding difference is between UTF16le and UTF16be |
|
** is a closer match than a function where the encoding difference is |
|
** between UTF8 and UTF16. |
|
** |
|
** ^Built-in functions may be overloaded by new application-defined functions. |
|
** |
|
** ^An application-defined function is permitted to call other |
|
** SQLite interfaces. However, such calls must not |
|
** close the database connection nor finalize or reset the prepared |
|
** statement in which the function is running. |
|
*/ |
|
SQLITE_API int sqlite3_create_function( |
|
sqlite3 *db, |
|
const char *zFunctionName, |
|
int nArg, |
|
int eTextRep, |
|
void *pApp, |
|
void (*xFunc)(sqlite3_context*,int,sqlite3_value**), |
|
void (*xStep)(sqlite3_context*,int,sqlite3_value**), |
|
void (*xFinal)(sqlite3_context*) |
|
); |
|
SQLITE_API int sqlite3_create_function16( |
|
sqlite3 *db, |
|
const void *zFunctionName, |
|
int nArg, |
|
int eTextRep, |
|
void *pApp, |
|
void (*xFunc)(sqlite3_context*,int,sqlite3_value**), |
|
void (*xStep)(sqlite3_context*,int,sqlite3_value**), |
|
void (*xFinal)(sqlite3_context*) |
|
); |
|
SQLITE_API int sqlite3_create_function_v2( |
|
sqlite3 *db, |
|
const char *zFunctionName, |
|
int nArg, |
|
int eTextRep, |
|
void *pApp, |
|
void (*xFunc)(sqlite3_context*,int,sqlite3_value**), |
|
void (*xStep)(sqlite3_context*,int,sqlite3_value**), |
|
void (*xFinal)(sqlite3_context*), |
|
void(*xDestroy)(void*) |
|
); |
|
|
|
/* |
|
** CAPI3REF: Text Encodings |
|
** |
|
** These constant define integer codes that represent the various |
|
** text encodings supported by SQLite. |
|
*/ |
|
#define SQLITE_UTF8 1 /* IMP: R-37514-35566 */ |
|
#define SQLITE_UTF16LE 2 /* IMP: R-03371-37637 */ |
|
#define SQLITE_UTF16BE 3 /* IMP: R-51971-34154 */ |
|
#define SQLITE_UTF16 4 /* Use native byte order */ |
|
#define SQLITE_ANY 5 /* Deprecated */ |
|
#define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */ |
|
|
|
/* |
|
** CAPI3REF: Function Flags |
|
** |
|
** These constants may be ORed together with the |
|
** [SQLITE_UTF8 | preferred text encoding] as the fourth argument |
|
** to [sqlite3_create_function()], [sqlite3_create_function16()], or |
|
** [sqlite3_create_function_v2()]. |
|
*/ |
|
#define SQLITE_DETERMINISTIC 0x800 |
|
|
|
/* |
|
** CAPI3REF: Deprecated Functions |
|
** DEPRECATED |
|
** |
|
** These functions are [deprecated]. In order to maintain |
|
** backwards compatibility with older code, these functions continue |
|
** to be supported. However, new applications should avoid |
|
** the use of these functions. To encourage programmers to avoid |
|
** these functions, we will not explain what they do. |
|
*/ |
|
#ifndef SQLITE_OMIT_DEPRECATED |
|
SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*); |
|
SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*); |
|
SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*); |
|
SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void); |
|
SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void); |
|
SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int), |
|
void*,sqlite3_int64); |
|
#endif |
|
|
|
/* |
|
** CAPI3REF: Obtaining SQL Values |
|
** METHOD: sqlite3_value |
|
** |
|
** The C-language implementation of SQL functions and aggregates uses |
|
** this set of interface routines to access the parameter values on |
|
** the function or aggregate. |
|
** |
|
** The xFunc (for scalar functions) or xStep (for aggregates) parameters |
|
** to [sqlite3_create_function()] and [sqlite3_create_function16()] |
|
** define callbacks that implement the SQL functions and aggregates. |
|
** The 3rd parameter to these callbacks is an array of pointers to |
|
** [protected sqlite3_value] objects. There is one [sqlite3_value] object for |
|
** each parameter to the SQL function. These routines are used to |
|
** extract values from the [sqlite3_value] objects. |
|
** |
|
** These routines work only with [protected sqlite3_value] objects. |
|
** Any attempt to use these routines on an [unprotected sqlite3_value] |
|
** object results in undefined behavior. |
|
** |
|
** ^These routines work just like the corresponding [column access functions] |
|
** except that these routines take a single [protected sqlite3_value] object |
|
** pointer instead of a [sqlite3_stmt*] pointer and an integer column number. |
|
** |
|
** ^The sqlite3_value_text16() interface extracts a UTF-16 string |
|
** in the native byte-order of the host machine. ^The |
|
** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces |
|
** extract UTF-16 strings as big-endian and little-endian respectively. |
|
** |
|
** ^(The sqlite3_value_numeric_type() interface attempts to apply |
|
** numeric affinity to the value. This means that an attempt is |
|
** made to convert the value to an integer or floating point. If |
|
** such a conversion is possible without loss of information (in other |
|
** words, if the value is a string that looks like a number) |
|
** then the conversion is performed. Otherwise no conversion occurs. |
|
** The [SQLITE_INTEGER | datatype] after conversion is returned.)^ |
|
** |
|
** Please pay particular attention to the fact that the pointer returned |
|
** from [sqlite3_value_blob()], [sqlite3_value_text()], or |
|
** [sqlite3_value_text16()] can be invalidated by a subsequent call to |
|
** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()], |
|
** or [sqlite3_value_text16()]. |
|
** |
|
** These routines must be called from the same thread as |
|
** the SQL function that supplied the [sqlite3_value*] parameters. |
|
*/ |
|
SQLITE_API const void *sqlite3_value_blob(sqlite3_value*); |
|
SQLITE_API int sqlite3_value_bytes(sqlite3_value*); |
|
SQLITE_API int sqlite3_value_bytes16(sqlite3_value*); |
|
SQLITE_API double sqlite3_value_double(sqlite3_value*); |
|
SQLITE_API int sqlite3_value_int(sqlite3_value*); |
|
SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*); |
|
SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*); |
|
SQLITE_API const void *sqlite3_value_text16(sqlite3_value*); |
|
SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*); |
|
SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*); |
|
SQLITE_API int sqlite3_value_type(sqlite3_value*); |
|
SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*); |
|
|
|
/* |
|
** CAPI3REF: Finding The Subtype Of SQL Values |
|
** METHOD: sqlite3_value |
|
** |
|
** The sqlite3_value_subtype(V) function returns the subtype for |
|
** an [application-defined SQL function] argument V. The subtype |
|
** information can be used to pass a limited amount of context from |
|
** one SQL function to another. Use the [sqlite3_result_subtype()] |
|
** routine to set the subtype for the return value of an SQL function. |
|
** |
|
** SQLite makes no use of subtype itself. It merely passes the subtype |
|
** from the result of one [application-defined SQL function] into the |
|
** input of another. |
|
*/ |
|
SQLITE_API unsigned int sqlite3_value_subtype(sqlite3_value*); |
|
|
|
/* |
|
** CAPI3REF: Copy And Free SQL Values |
|
** METHOD: sqlite3_value |
|
** |
|
** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value] |
|
** object D and returns a pointer to that copy. ^The [sqlite3_value] returned |
|
** is a [protected sqlite3_value] object even if the input is not. |
|
** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a |
|
** memory allocation fails. |
|
** |
|
** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object |
|
** previously obtained from [sqlite3_value_dup()]. ^If V is a NULL pointer |
|
** then sqlite3_value_free(V) is a harmless no-op. |
|
*/ |
|
SQLITE_API sqlite3_value *sqlite3_value_dup(const sqlite3_value*); |
|
SQLITE_API void sqlite3_value_free(sqlite3_value*); |
|
|
|
/* |
|
** CAPI3REF: Obtain Aggregate Function Context |
|
** METHOD: sqlite3_context |
|
** |
|
** Implementations of aggregate SQL functions use this |
|
** routine to allocate memory for storing their state. |
|
** |
|
** ^The first time the sqlite3_aggregate_context(C,N) routine is called |
|
** for a particular aggregate function, SQLite |
|
** allocates N of memory, zeroes out that memory, and returns a pointer |
|
** to the new memory. ^On second and subsequent calls to |
|
** sqlite3_aggregate_context() for the same aggregate function instance, |
|
** the same buffer is returned. Sqlite3_aggregate_context() is normally |
|
** called once for each invocation of the xStep callback and then one |
|
** last time when the xFinal callback is invoked. ^(When no rows match |
|
** an aggregate query, the xStep() callback of the aggregate function |
|
** implementation is never called and xFinal() is called exactly once. |
|
** In those cases, sqlite3_aggregate_context() might be called for the |
|
** first time from within xFinal().)^ |
|
** |
|
** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer |
|
** when first called if N is less than or equal to zero or if a memory |
|
** allocate error occurs. |
|
** |
|
** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is |
|
** determined by the N parameter on first successful call. Changing the |
|
** value of N in subsequent call to sqlite3_aggregate_context() within |
|
** the same aggregate function instance will not resize the memory |
|
** allocation.)^ Within the xFinal callback, it is customary to set |
|
** N=0 in calls to sqlite3_aggregate_context(C,N) so that no |
|
** pointless memory allocations occur. |
|
** |
|
** ^SQLite automatically frees the memory allocated by |
|
** sqlite3_aggregate_context() when the aggregate query concludes. |
|
** |
|
** The first parameter must be a copy of the |
|
** [sqlite3_context | SQL function context] that is the first parameter |
|
** to the xStep or xFinal callback routine that implements the aggregate |
|
** function. |
|
** |
|
** This routine must be called from the same thread in which |
|
** the aggregate SQL function is running. |
|
*/ |
|
SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes); |
|
|
|
/* |
|
** CAPI3REF: User Data For Functions |
|
** METHOD: sqlite3_context |
|
** |
|
** ^The sqlite3_user_data() interface returns a copy of |
|
** the pointer that was the pUserData parameter (the 5th parameter) |
|
** of the [sqlite3_create_function()] |
|
** and [sqlite3_create_function16()] routines that originally |
|
** registered the application defined function. |
|
** |
|
** This routine must be called from the same thread in which |
|
** the application-defined function is running. |
|
*/ |
|
SQLITE_API void *sqlite3_user_data(sqlite3_context*); |
|
|
|
/* |
|
** CAPI3REF: Database Connection For Functions |
|
** METHOD: sqlite3_context |
|
** |
|
** ^The sqlite3_context_db_handle() interface returns a copy of |
|
** the pointer to the [database connection] (the 1st parameter) |
|
** of the [sqlite3_create_function()] |
|
** and [sqlite3_create_function16()] routines that originally |
|
** registered the application defined function. |
|
*/ |
|
SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*); |
|
|
|
/* |
|
** CAPI3REF: Function Auxiliary Data |
|
** METHOD: sqlite3_context |
|
** |
|
** These functions may be used by (non-aggregate) SQL functions to |
|
** associate metadata with argument values. If the same value is passed to |
|
** multiple invocations of the same SQL function during query execution, under |
|
** some circumstances the associated metadata may be preserved. An example |
|
** of where this might be useful is in a regular-expression matching |
|
** function. The compiled version of the regular expression can be stored as |
|
** metadata associated with the pattern string. |
|
** Then as long as the pattern string remains the same, |
|
** the compiled regular expression can be reused on multiple |
|
** invocations of the same function. |
|
** |
|
** ^The sqlite3_get_auxdata() interface returns a pointer to the metadata |
|
** associated by the sqlite3_set_auxdata() function with the Nth argument |
|
** value to the application-defined function. ^If there is no metadata |
|
** associated with the function argument, this sqlite3_get_auxdata() interface |
|
** returns a NULL pointer. |
|
** |
|
** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th |
|
** argument of the application-defined function. ^Subsequent |
|
** calls to sqlite3_get_auxdata(C,N) return P from the most recent |
|
** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or |
|
** NULL if the metadata has been discarded. |
|
** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL, |
|
** SQLite will invoke the destructor function X with parameter P exactly |
|
** once, when the metadata is discarded. |
|
** SQLite is free to discard the metadata at any time, including: <ul> |
|
** <li> ^(when the corresponding function parameter changes)^, or |
|
** <li> ^(when [sqlite3_reset()] or [sqlite3_finalize()] is called for the |
|
** SQL statement)^, or |
|
** <li> ^(when sqlite3_set_auxdata() is invoked again on the same |
|
** parameter)^, or |
|
** <li> ^(during the original sqlite3_set_auxdata() call when a memory |
|
** allocation error occurs.)^ </ul> |
|
** |
|
** Note the last bullet in particular. The destructor X in |
|
** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the |
|
** sqlite3_set_auxdata() interface even returns. Hence sqlite3_set_auxdata() |
|
** should be called near the end of the function implementation and the |
|
** function implementation should not make any use of P after |
|
** sqlite3_set_auxdata() has been called. |
|
** |
|
** ^(In practice, metadata is preserved between function calls for |
|
** function parameters that are compile-time constants, including literal |
|
** values and [parameters] and expressions composed from the same.)^ |
|
** |
|
** These routines must be called from the same thread in which |
|
** the SQL function is running. |
|
*/ |
|
SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N); |
|
SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*)); |
|
|
|
|
|
/* |
|
** CAPI3REF: Constants Defining Special Destructor Behavior |
|
** |
|
** These are special values for the destructor that is passed in as the |
|
** final argument to routines like [sqlite3_result_blob()]. ^If the destructor |
|
** argument is SQLITE_STATIC, it means that the content pointer is constant |
|
** and will never change. It does not need to be destroyed. ^The |
|
** SQLITE_TRANSIENT value means that the content will likely change in |
|
** the near future and that SQLite should make its own private copy of |
|
** the content before returning. |
|
** |
|
** The typedef is necessary to work around problems in certain |
|
** C++ compilers. |
|
*/ |
|
typedef void (*sqlite3_destructor_type)(void*); |
|
#define SQLITE_STATIC ((sqlite3_destructor_type)0) |
|
#define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1) |
|
|
|
/* |
|
** CAPI3REF: Setting The Result Of An SQL Function |
|
** METHOD: sqlite3_context |
|
** |
|
** These routines are used by the xFunc or xFinal callbacks that |
|
** implement SQL functions and aggregates. See |
|
** [sqlite3_create_function()] and [sqlite3_create_function16()] |
|
** for additional information. |
|
** |
|
** These functions work very much like the [parameter binding] family of |
|
** functions used to bind values to host parameters in prepared statements. |
|
** Refer to the [SQL parameter] documentation for additional information. |
|
** |
|
** ^The sqlite3_result_blob() interface sets the result from |
|
** an application-defined function to be the BLOB whose content is pointed |
|
** to by the second parameter and which is N bytes long where N is the |
|
** third parameter. |
|
** |
|
** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N) |
|
** interfaces set the result of the application-defined function to be |
|
** a BLOB containing all zero bytes and N bytes in size. |
|
** |
|
** ^The sqlite3_result_double() interface sets the result from |
|
** an application-defined function to be a floating point value specified |
|
** by its 2nd argument. |
|
** |
|
** ^The sqlite3_result_error() and sqlite3_result_error16() functions |
|
** cause the implemented SQL function to throw an exception. |
|
** ^SQLite uses the string pointed to by the |
|
** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16() |
|
** as the text of an error message. ^SQLite interprets the error |
|
** message string from sqlite3_result_error() as UTF-8. ^SQLite |
|
** interprets the string from sqlite3_result_error16() as UTF-16 in native |
|
** byte order. ^If the third parameter to sqlite3_result_error() |
|
** or sqlite3_result_error16() is negative then SQLite takes as the error |
|
** message all text up through the first zero character. |
|
** ^If the third parameter to sqlite3_result_error() or |
|
** sqlite3_result_error16() is non-negative then SQLite takes that many |
|
** bytes (not characters) from the 2nd parameter as the error message. |
|
** ^The sqlite3_result_error() and sqlite3_result_error16() |
|
** routines make a private copy of the error message text before |
|
** they return. Hence, the calling function can deallocate or |
|
** modify the text after they return without harm. |
|
** ^The sqlite3_result_error_code() function changes the error code |
|
** returned by SQLite as a result of an error in a function. ^By default, |
|
** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error() |
|
** or sqlite3_result_error16() resets the error code to SQLITE_ERROR. |
|
** |
|
** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an |
|
** error indicating that a string or BLOB is too long to represent. |
|
** |
|
** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an |
|
** error indicating that a memory allocation failed. |
|
** |
|
** ^The sqlite3_result_int() interface sets the return value |
|
** of the application-defined function to be the 32-bit signed integer |
|
** value given in the 2nd argument. |
|
** ^The sqlite3_result_int64() interface sets the return value |
|
** of the application-defined function to be the 64-bit signed integer |
|
** value given in the 2nd argument. |
|
** |
|
** ^The sqlite3_result_null() interface sets the return value |
|
** of the application-defined function to be NULL. |
|
** |
|
** ^The sqlite3_result_text(), sqlite3_result_text16(), |
|
** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces |
|
** set the return value of the application-defined function to be |
|
** a text string which is represented as UTF-8, UTF-16 native byte order, |
|
** UTF-16 little endian, or UTF-16 big endian, respectively. |
|
** ^The sqlite3_result_text64() interface sets the return value of an |
|
** application-defined function to be a text string in an encoding |
|
** specified by the fifth (and last) parameter, which must be one |
|
** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]. |
|
** ^SQLite takes the text result from the application from |
|
** the 2nd parameter of the sqlite3_result_text* interfaces. |
|
** ^If the 3rd parameter to the sqlite3_result_text* interfaces |
|
** is negative, then SQLite takes result text from the 2nd parameter |
|
** through the first zero character. |
|
** ^If the 3rd parameter to the sqlite3_result_text* interfaces |
|
** is non-negative, then as many bytes (not characters) of the text |
|
** pointed to by the 2nd parameter are taken as the application-defined |
|
** function result. If the 3rd parameter is non-negative, then it |
|
** must be the byte offset into the string where the NUL terminator would |
|
** appear if the string where NUL terminated. If any NUL characters occur |
|
** in the string at a byte offset that is less than the value of the 3rd |
|
** parameter, then the resulting string will contain embedded NULs and the |
|
** result of expressions operating on strings with embedded NULs is undefined. |
|
** ^If the 4th parameter to the sqlite3_result_text* interfaces |
|
** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that |
|
** function as the destructor on the text or BLOB result when it has |
|
** finished using that result. |
|
** ^If the 4th parameter to the sqlite3_result_text* interfaces or to |
|
** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite |
|
** assumes that the text or BLOB result is in constant space and does not |
|
** copy the content of the parameter nor call a destructor on the content |
|
** when it has finished using that result. |
|
** ^If the 4th parameter to the sqlite3_result_text* interfaces |
|
** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT |
|
** then SQLite makes a copy of the result into space obtained from |
|
** from [sqlite3_malloc()] before it returns. |
|
** |
|
** ^The sqlite3_result_value() interface sets the result of |
|
** the application-defined function to be a copy of the |
|
** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The |
|
** sqlite3_result_value() interface makes a copy of the [sqlite3_value] |
|
** so that the [sqlite3_value] specified in the parameter may change or |
|
** be deallocated after sqlite3_result_value() returns without harm. |
|
** ^A [protected sqlite3_value] object may always be used where an |
|
** [unprotected sqlite3_value] object is required, so either |
|
** kind of [sqlite3_value] object can be used with this interface. |
|
** |
|
** If these routines are called from within the different thread |
|
** than the one containing the application-defined function that received |
|
** the [sqlite3_context] pointer, the results are undefined. |
|
*/ |
|
SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*)); |
|
SQLITE_API void sqlite3_result_blob64(sqlite3_context*,const void*, |
|
sqlite3_uint64,void(*)(void*)); |
|
SQLITE_API void sqlite3_result_double(sqlite3_context*, double); |
|
SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int); |
|
SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int); |
|
SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*); |
|
SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*); |
|
SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int); |
|
SQLITE_API void sqlite3_result_int(sqlite3_context*, int); |
|
SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64); |
|
SQLITE_API void sqlite3_result_null(sqlite3_context*); |
|
SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*)); |
|
SQLITE_API void sqlite3_result_text64(sqlite3_context*, const char*,sqlite3_uint64, |
|
void(*)(void*), unsigned char encoding); |
|
SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*)); |
|
SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*)); |
|
SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*)); |
|
SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*); |
|
SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n); |
|
SQLITE_API int sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n); |
|
|
|
|
|
/* |
|
** CAPI3REF: Setting The Subtype Of An SQL Function |
|
** METHOD: sqlite3_context |
|
** |
|
** The sqlite3_result_subtype(C,T) function causes the subtype of |
|
** the result from the [application-defined SQL function] with |
|
** [sqlite3_context] C to be the value T. Only the lower 8 bits |
|
** of the subtype T are preserved in current versions of SQLite; |
|
** higher order bits are discarded. |
|
** The number of subtype bytes preserved by SQLite might increase |
|
** in future releases of SQLite. |
|
*/ |
|
SQLITE_API void sqlite3_result_subtype(sqlite3_context*,unsigned int); |
|
|
|
/* |
|
** CAPI3REF: Define New Collating Sequences |
|
** METHOD: sqlite3 |
|
** |
|
** ^These functions add, remove, or modify a [collation] associated |
|
** with the [database connection] specified as the first argument. |
|
** |
|
** ^The name of the collation is a UTF-8 string |
|
** for sqlite3_create_collation() and sqlite3_create_collation_v2() |
|
** and a UTF-16 string in native byte order for sqlite3_create_collation16(). |
|
** ^Collation names that compare equal according to [sqlite3_strnicmp()] are |
|
** considered to be the same name. |
|
** |
|
** ^(The third argument (eTextRep) must be one of the constants: |
|
** <ul> |
|
** <li> [SQLITE_UTF8], |
|
** <li> [SQLITE_UTF16LE], |
|
** <li> [SQLITE_UTF16BE], |
|
** <li> [SQLITE_UTF16], or |
|
** <li> [SQLITE_UTF16_ALIGNED]. |
|
** </ul>)^ |
|
** ^The eTextRep argument determines the encoding of strings passed |
|
** to the collating function callback, xCallback. |
|
** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep |
|
** force strings to be UTF16 with native byte order. |
|
** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin |
|
** on an even byte address. |
|
** |
|
** ^The fourth argument, pArg, is an application data pointer that is passed |
|
** through as the first argument to the collating function callback. |
|
** |
|
** ^The fifth argument, xCallback, is a pointer to the collating function. |
|
** ^Multiple collating functions can be registered using the same name but |
|
** with different eTextRep parameters and SQLite will use whichever |
|
** function requires the least amount of data transformation. |
|
** ^If the xCallback argument is NULL then the collating function is |
|
** deleted. ^When all collating functions having the same name are deleted, |
|
** that collation is no longer usable. |
|
** |
|
** ^The collating function callback is invoked with a copy of the pArg |
|
** application data pointer and with two strings in the encoding specified |
|
** by the eTextRep argument. The collating function must return an |
|
** integer that is negative, zero, or positive |
|
** if the first string is less than, equal to, or greater than the second, |
|
** respectively. A collating function must always return the same answer |
|
** given the same inputs. If two or more collating functions are registered |
|
** to the same collation name (using different eTextRep values) then all |
|
** must give an equivalent answer when invoked with equivalent strings. |
|
** The collating function must obey the following properties for all |
|
** strings A, B, and C: |
|
** |
|
** <ol> |
|
** <li> If A==B then B==A. |
|
** <li> If A==B and B==C then A==C. |
|
** <li> If A<B THEN B>A. |
|
** <li> If A<B and B<C then A<C. |
|
** </ol> |
|
** |
|
** If a collating function fails any of the above constraints and that |
|
** collating function is registered and used, then the behavior of SQLite |
|
** is undefined. |
|
** |
|
** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation() |
|
** with the addition that the xDestroy callback is invoked on pArg when |
|
** the collating function is deleted. |
|
** ^Collating functions are deleted when they are overridden by later |
|
** calls to the collation creation functions or when the |
|
** [database connection] is closed using [sqlite3_close()]. |
|
** |
|
** ^The xDestroy callback is <u>not</u> called if the |
|
** sqlite3_create_collation_v2() function fails. Applications that invoke |
|
** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should |
|
** check the return code and dispose of the application data pointer |
|
** themselves rather than expecting SQLite to deal with it for them. |
|
** This is different from every other SQLite interface. The inconsistency |
|
** is unfortunate but cannot be changed without breaking backwards |
|
** compatibility. |
|
** |
|
** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()]. |
|
*/ |
|
SQLITE_API int sqlite3_create_collation( |
|
sqlite3*, |
|
const char *zName, |
|
int eTextRep, |
|
void *pArg, |
|
int(*xCompare)(void*,int,const void*,int,const void*) |
|
); |
|
SQLITE_API int sqlite3_create_collation_v2( |
|
sqlite3*, |
|
const char *zName, |
|
int eTextRep, |
|
void *pArg, |
|
int(*xCompare)(void*,int,const void*,int,const void*), |
|
void(*xDestroy)(void*) |
|
); |
|
SQLITE_API int sqlite3_create_collation16( |
|
sqlite3*, |
|
const void *zName, |
|
int eTextRep, |
|
void *pArg, |
|
int(*xCompare)(void*,int,const void*,int,const void*) |
|
); |
|
|
|
/* |
|
** CAPI3REF: Collation Needed Callbacks |
|
** METHOD: sqlite3 |
|
** |
|
** ^To avoid having to register all collation sequences before a database |
|
** can be used, a single callback function may be registered with the |
|
** [database connection] to be invoked whenever an undefined collation |
|
** sequence is required. |
|
** |
|
** ^If the function is registered using the sqlite3_collation_needed() API, |
|
** then it is passed the names of undefined collation sequences as strings |
|
** encoded in UTF-8. ^If sqlite3_collation_needed16() is used, |
|
** the names are passed as UTF-16 in machine native byte order. |
|
** ^A call to either function replaces the existing collation-needed callback. |
|
** |
|
** ^(When the callback is invoked, the first argument passed is a copy |
|
** of the second argument to sqlite3_collation_needed() or |
|
** sqlite3_collation_needed16(). The second argument is the database |
|
** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE], |
|
** or [SQLITE_UTF16LE], indicating the most desirable form of the collation |
|
** sequence function required. The fourth parameter is the name of the |
|
** required collation sequence.)^ |
|
** |
|
** The callback function should register the desired collation using |
|
** [sqlite3_create_collation()], [sqlite3_create_collation16()], or |
|
** [sqlite3_create_collation_v2()]. |
|
*/ |
|
SQLITE_API int sqlite3_collation_needed( |
|
sqlite3*, |
|
void*, |
|
void(*)(void*,sqlite3*,int eTextRep,const char*) |
|
); |
|
SQLITE_API int sqlite3_collation_needed16( |
|
sqlite3*, |
|
void*, |
|
void(*)(void*,sqlite3*,int eTextRep,const void*) |
|
); |
|
|
|
#ifdef SQLITE_HAS_CODEC |
|
/* |
|
** Specify the key for an encrypted database. This routine should be |
|
** called right after sqlite3_open(). |
|
** |
|
** The code to implement this API is not available in the public release |
|
** of SQLite. |
|
*/ |
|
SQLITE_API int sqlite3_key( |
|
sqlite3 *db, /* Database to be rekeyed */ |
|
const void *pKey, int nKey /* The key */ |
|
); |
|
SQLITE_API int sqlite3_key_v2( |
|
sqlite3 *db, /* Database to be rekeyed */ |
|
const char *zDbName, /* Name of the database */ |
|
const void *pKey, int nKey /* The key */ |
|
); |
|
|
|
/* |
|
** Change the key on an open database. If the current database is not |
|
** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the |
|
** database is decrypted. |
|
** |
|
** The code to implement this API is not available in the public release |
|
** of SQLite. |
|
*/ |
|
SQLITE_API int sqlite3_rekey( |
|
sqlite3 *db, /* Database to be rekeyed */ |
|
const void *pKey, int nKey /* The new key */ |
|
); |
|
SQLITE_API int sqlite3_rekey_v2( |
|
sqlite3 *db, /* Database to be rekeyed */ |
|
const char *zDbName, /* Name of the database */ |
|
const void *pKey, int nKey /* The new key */ |
|
); |
|
|
|
/* |
|
** Specify the activation key for a SEE database. Unless |
|
** activated, none of the SEE routines will work. |
|
*/ |
|
SQLITE_API void sqlite3_activate_see( |
|
const char *zPassPhrase /* Activation phrase */ |
|
); |
|
#endif |
|
|
|
#ifdef SQLITE_ENABLE_CEROD |
|
/* |
|
** Specify the activation key for a CEROD database. Unless |
|
** activated, none of the CEROD routines will work. |
|
*/ |
|
SQLITE_API void sqlite3_activate_cerod( |
|
const char *zPassPhrase /* Activation phrase */ |
|
); |
|
#endif |
|
|
|
/* |
|
** CAPI3REF: Suspend Execution For A Short Time |
|
** |
|
** The sqlite3_sleep() function causes the current thread to suspend execution |
|
** for at least a number of milliseconds specified in its parameter. |
|
** |
|
** If the operating system does not support sleep requests with |
|
** millisecond time resolution, then the time will be rounded up to |
|
** the nearest second. The number of milliseconds of sleep actually |
|
** requested from the operating system is returned. |
|
** |
|
** ^SQLite implements this interface by calling the xSleep() |
|
** method of the default [sqlite3_vfs] object. If the xSleep() method |
|
** of the default VFS is not implemented correctly, or not implemented at |
|
** all, then the behavior of sqlite3_sleep() may deviate from the description |
|
** in the previous paragraphs. |
|
*/ |
|
SQLITE_API int sqlite3_sleep(int); |
|
|
|
/* |
|
** CAPI3REF: Name Of The Folder Holding Temporary Files |
|
** |
|
** ^(If this global variable is made to point to a string which is |
|
** the name of a folder (a.k.a. directory), then all temporary files |
|
** created by SQLite when using a built-in [sqlite3_vfs | VFS] |
|
** will be placed in that directory.)^ ^If this variable |
|
** is a NULL pointer, then SQLite performs a search for an appropriate |
|
** temporary file directory. |
|
** |
|
** Applications are strongly discouraged from using this global variable. |
|
** It is required to set a temporary folder on Windows Runtime (WinRT). |
|
** But for all other platforms, it is highly recommended that applications |
|
** neither read nor write this variable. This global variable is a relic |
|
** that exists for backwards compatibility of legacy applications and should |
|
** be avoided in new projects. |
|
** |
|
** It is not safe to read or modify this variable in more than one |
|
** thread at a time. It is not safe to read or modify this variable |
|
** if a [database connection] is being used at the same time in a separate |
|
** thread. |
|
** It is intended that this variable be set once |
|
** as part of process initialization and before any SQLite interface |
|
** routines have been called and that this variable remain unchanged |
|
** thereafter. |
|
** |
|
** ^The [temp_store_directory pragma] may modify this variable and cause |
|
** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, |
|
** the [temp_store_directory pragma] always assumes that any string |
|
** that this variable points to is held in memory obtained from |
|
** [sqlite3_malloc] and the pragma may attempt to free that memory |
|
** using [sqlite3_free]. |
|
** Hence, if this variable is modified directly, either it should be |
|
** made NULL or made to point to memory obtained from [sqlite3_malloc] |
|
** or else the use of the [temp_store_directory pragma] should be avoided. |
|
** Except when requested by the [temp_store_directory pragma], SQLite |
|
** does not free the memory that sqlite3_temp_directory points to. If |
|
** the application wants that memory to be freed, it must do |
|
** so itself, taking care to only do so after all [database connection] |
|
** objects have been destroyed. |
|
** |
|
** <b>Note to Windows Runtime users:</b> The temporary directory must be set |
|
** prior to calling [sqlite3_open] or [sqlite3_open_v2]. Otherwise, various |
|
** features that require the use of temporary files may fail. Here is an |
|
** example of how to do this using C++ with the Windows Runtime: |
|
** |
|
** <blockquote><pre> |
|
** LPCWSTR zPath = Windows::Storage::ApplicationData::Current-> |
|
** TemporaryFolder->Path->Data(); |
|
** char zPathBuf[MAX_PATH + 1]; |
|
** memset(zPathBuf, 0, sizeof(zPathBuf)); |
|
** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf), |
|
** NULL, NULL); |
|
** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf); |
|
** </pre></blockquote> |
|
*/ |
|
SQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory; |
|
|
|
/* |
|
** CAPI3REF: Name Of The Folder Holding Database Files |
|
** |
|
** ^(If this global variable is made to point to a string which is |
|
** the name of a folder (a.k.a. directory), then all database files |
|
** specified with a relative pathname and created or accessed by |
|
** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed |
|
** to be relative to that directory.)^ ^If this variable is a NULL |
|
** pointer, then SQLite assumes that all database files specified |
|
** with a relative pathname are relative to the current directory |
|
** for the process. Only the windows VFS makes use of this global |
|
** variable; it is ignored by the unix VFS. |
|
** |
|
** Changing the value of this variable while a database connection is |
|
** open can result in a corrupt database. |
|
** |
|
** It is not safe to read or modify this variable in more than one |
|
** thread at a time. It is not safe to read or modify this variable |
|
** if a [database connection] is being used at the same time in a separate |
|
** thread. |
|
** It is intended that this variable be set once |
|
** as part of process initialization and before any SQLite interface |
|
** routines have been called and that this variable remain unchanged |
|
** thereafter. |
|
** |
|
** ^The [data_store_directory pragma] may modify this variable and cause |
|
** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, |
|
** the [data_store_directory pragma] always assumes that any string |
|
** that this variable points to is held in memory obtained from |
|
** [sqlite3_malloc] and the pragma may attempt to free that memory |
|
** using [sqlite3_free]. |
|
** Hence, if this variable is modified directly, either it should be |
|
** made NULL or made to point to memory obtained from [sqlite3_malloc] |
|
** or else the use of the [data_store_directory pragma] should be avoided. |
|
*/ |
|
SQLITE_API SQLITE_EXTERN char *sqlite3_data_directory; |
|
|
|
/* |
|
** CAPI3REF: Test For Auto-Commit Mode |
|
** KEYWORDS: {autocommit mode} |
|
** METHOD: sqlite3 |
|
** |
|
** ^The sqlite3_get_autocommit() interface returns non-zero or |
|
** zero if the given database connection is or is not in autocommit mode, |
|
** respectively. ^Autocommit mode is on by default. |
|
** ^Autocommit mode is disabled by a [BEGIN] statement. |
|
** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK]. |
|
** |
|
** If certain kinds of errors occur on a statement within a multi-statement |
|
** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR], |
|
** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the |
|
** transaction might be rolled back automatically. The only way to |
|
** find out whether SQLite automatically rolled back the transaction after |
|
** an error is to use this function. |
|
** |
|
** If another thread changes the autocommit status of the database |
|
** connection while this routine is running, then the return value |
|
** is undefined. |
|
*/ |
|
SQLITE_API int sqlite3_get_autocommit(sqlite3*); |
|
|
|
/* |
|
** CAPI3REF: Find The Database Handle Of A Prepared Statement |
|
** METHOD: sqlite3_stmt |
|
** |
|
** ^The sqlite3_db_handle interface returns the [database connection] handle |
|
** to which a [prepared statement] belongs. ^The [database connection] |
|
** returned by sqlite3_db_handle is the same [database connection] |
|
** that was the first argument |
|
** to the [sqlite3_prepare_v2()] call (or its variants) that was used to |
|
** create the statement in the first place. |
|
*/ |
|
SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*); |
|
|
|
/* |
|
** CAPI3REF: Return The Filename For A Database Connection |
|
** METHOD: sqlite3 |
|
** |
|
** ^The sqlite3_db_filename(D,N) interface returns a pointer to a filename |
|
** associated with database N of connection D. ^The main database file |
|
** has the name "main". If there is no attached database N on the database |
|
** connection D, or if database N is a temporary or in-memory database, then |
|
** a NULL pointer is returned. |
|
** |
|
** ^The filename returned by this function is the output of the |
|
** xFullPathname method of the [VFS]. ^In other words, the filename |
|
** will be an absolute pathname, even if the filename used |
|
** to open the database originally was a URI or relative pathname. |
|
*/ |
|
SQLITE_API const char *sqlite3_db_filename(sqlite3 *db, const char *zDbName); |
|
|
|
/* |
|
** CAPI3REF: Determine if a database is read-only |
|
** METHOD: sqlite3 |
|
** |
|
** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N |
|
** of connection D is read-only, 0 if it is read/write, or -1 if N is not |
|
** the name of a database on connection D. |
|
*/ |
|
SQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName); |
|
|
|
/* |
|
** CAPI3REF: Find the next prepared statement |
|
** METHOD: sqlite3 |
|
** |
|
** ^This interface returns a pointer to the next [prepared statement] after |
|
** pStmt associated with the [database connection] pDb. ^If pStmt is NULL |
|
** then this interface returns a pointer to the first prepared statement |
|
** associated with the database connection pDb. ^If no prepared statement |
|
** satisfies the conditions of this routine, it returns NULL. |
|
** |
|
** The [database connection] pointer D in a call to |
|
** [sqlite3_next_stmt(D,S)] must refer to an open database |
|
** connection and in particular must not be a NULL pointer. |
|
*/ |
|
SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt); |
|
|
|
/* |
|
** CAPI3REF: Commit And Rollback Notification Callbacks |
|
** METHOD: sqlite3 |
|
** |
|
** ^The sqlite3_commit_hook() interface registers a callback |
|
** function to be invoked whenever a transaction is [COMMIT | committed]. |
|
** ^Any callback set by a previous call to sqlite3_commit_hook() |
|
** for the same database connection is overridden. |
|
** ^The sqlite3_rollback_hook() interface registers a callback |
|
** function to be invoked whenever a transaction is [ROLLBACK | rolled back]. |
|
** ^Any callback set by a previous call to sqlite3_rollback_hook() |
|
** for the same database connection is overridden. |
|
** ^The pArg argument is passed through to the callback. |
|
** ^If the callback on a commit hook function returns non-zero, |
|
** then the commit is converted into a rollback. |
|
** |
|
** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions |
|
** return the P argument from the previous call of the same function |
|
** on the same [database connection] D, or NULL for |
|
** the first call for each function on D. |
|
** |
|
** The commit and rollback hook callbacks are not reentrant. |
|
** The callback implementation must not do anything that will modify |
|
** the database connection that invoked the callback. Any actions |
|
** to modify the database connection must be deferred until after the |
|
** completion of the [sqlite3_step()] call that triggered the commit |
|
** or rollback hook in the first place. |
|
** Note that running any other SQL statements, including SELECT statements, |
|
** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify |
|
** the database connections for the meaning of "modify" in this paragraph. |
|
** |
|
** ^Registering a NULL function disables the callback. |
|
** |
|
** ^When the commit hook callback routine returns zero, the [COMMIT] |
|
** operation is allowed to continue normally. ^If the commit hook |
|
** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK]. |
|
** ^The rollback hook is invoked on a rollback that results from a commit |
|
** hook returning non-zero, just as it would be with any other rollback. |
|
** |
|
** ^For the purposes of this API, a transaction is said to have been |
|
** rolled back if an explicit "ROLLBACK" statement is executed, or |
|
** an error or constraint causes an implicit rollback to occur. |
|
** ^The rollback callback is not invoked if a transaction is |
|
** automatically rolled back because the database connection is closed. |
|
** |
|
** See also the [sqlite3_update_hook()] interface. |
|
*/ |
|
SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*); |
|
SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*); |
|
|
|
/* |
|
** CAPI3REF: Data Change Notification Callbacks |
|
** METHOD: sqlite3 |
|
** |
|
** ^The sqlite3_update_hook() interface registers a callback function |
|
** with the [database connection] identified by the first argument |
|
** to be invoked whenever a row is updated, inserted or deleted in |
|
** a [rowid table]. |
|
** ^Any callback set by a previous call to this function |
|
** for the same database connection is overridden. |
|
** |
|
** ^The second argument is a pointer to the function to invoke when a |
|
** row is updated, inserted or deleted in a rowid table. |
|
** ^The first argument to the callback is a copy of the third argument |
|
** to sqlite3_update_hook(). |
|
** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE], |
|
** or [SQLITE_UPDATE], depending on the operation that caused the callback |
|
** to be invoked. |
|
** ^The third and fourth arguments to the callback contain pointers to the |
|
** database and table name containing the affected row. |
|
** ^The final callback parameter is the [rowid] of the row. |
|
** ^In the case of an update, this is the [rowid] after the update takes place. |
|
** |
|
** ^(The update hook is not invoked when internal system tables are |
|
** modified (i.e. sqlite_master and sqlite_sequence).)^ |
|
** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified. |
|
** |
|
** ^In the current implementation, the update hook |
|
** is not invoked when duplication rows are deleted because of an |
|
** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook |
|
** invoked when rows are deleted using the [truncate optimization]. |
|
** The exceptions defined in this paragraph might change in a future |
|
** release of SQLite. |
|
** |
|
** The update hook implementation must not do anything that will modify |
|
** the database connection that invoked the update hook. Any actions |
|
** to modify the database connection must be deferred until after the |
|
** completion of the [sqlite3_step()] call that triggered the update hook. |
|
** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their |
|
** database connections for the meaning of "modify" in this paragraph. |
|
** |
|
** ^The sqlite3_update_hook(D,C,P) function |
|
** returns the P argument from the previous call |
|
** on the same [database connection] D, or NULL for |
|
** the first call on D. |
|
** |
|
** See also the [sqlite3_commit_hook()], [sqlite3_rollback_hook()], |
|
** and [sqlite3_preupdate_hook()] interfaces. |
|
*/ |
|
SQLITE_API void *sqlite3_update_hook( |
|
sqlite3*, |
|
void(*)(void *,int ,char const *,char const *,sqlite3_int64), |
|
void* |
|
); |
|
|
|
/* |
|
** CAPI3REF: Enable Or Disable Shared Pager Cache |
|
** |
|
** ^(This routine enables or disables the sharing of the database cache |
|
** and schema data structures between [database connection | connections] |
|
** to the same database. Sharing is enabled if the argument is true |
|
** and disabled if the argument is false.)^ |
|
** |
|
** ^Cache sharing is enabled and disabled for an entire process. |
|
** This is a change as of SQLite [version 3.5.0] ([dateof:3.5.0]). |
|
** In prior versions of SQLite, |
|
** sharing was enabled or disabled for each thread separately. |
|
** |
|
** ^(The cache sharing mode set by this interface effects all subsequent |
|
** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()]. |
|
** Existing database connections continue use the sharing mode |
|
** that was in effect at the time they were opened.)^ |
|
** |
|
** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled |
|
** successfully. An [error code] is returned otherwise.)^ |
|
** |
|
** ^Shared cache is disabled by default. But this might change in |
|
** future releases of SQLite. Applications that care about shared |
|
** cache setting should set it explicitly. |
|
** |
|
** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0 |
|
** and will always return SQLITE_MISUSE. On those systems, |
|
** shared cache mode should be enabled per-database connection via |
|
** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE]. |
|
** |
|
** This interface is threadsafe on processors where writing a |
|
** 32-bit integer is atomic. |
|
** |
|
** See Also: [SQLite Shared-Cache Mode] |
|
*/ |
|
SQLITE_API int sqlite3_enable_shared_cache(int); |
|
|
|
/* |
|
** CAPI3REF: Attempt To Free Heap Memory |
|
** |
|
** ^The sqlite3_release_memory() interface attempts to free N bytes |
|
** of heap memory by deallocating non-essential memory allocations |
|
** held by the database library. Memory used to cache database |
|
** pages to improve performance is an example of non-essential memory. |
|
** ^sqlite3_release_memory() returns the number of bytes actually freed, |
|
** which might be more or less than the amount requested. |
|
** ^The sqlite3_release_memory() routine is a no-op returning zero |
|
** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT]. |
|
** |
|
** See also: [sqlite3_db_release_memory()] |
|
*/ |
|
SQLITE_API int sqlite3_release_memory(int); |
|
|
|
/* |
|
** CAPI3REF: Free Memory Used By A Database Connection |
|
** METHOD: sqlite3 |
|
** |
|
** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap |
|
** memory as possible from database connection D. Unlike the |
|
** [sqlite3_release_memory()] interface, this interface is in effect even |
|
** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is |
|
** omitted. |
|
** |
|
** See also: [sqlite3_release_memory()] |
|
*/ |
|
SQLITE_API int sqlite3_db_release_memory(sqlite3*); |
|
|
|
/* |
|
** CAPI3REF: Impose A Limit On Heap Size |
|
** |
|
** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the |
|
** soft limit on the amount of heap memory that may be allocated by SQLite. |
|
** ^SQLite strives to keep heap memory utilization below the soft heap |
|
** limit by reducing the number of pages held in the page cache |
|
** as heap memory usages approaches the limit. |
|
** ^The soft heap limit is "soft" because even though SQLite strives to stay |
|
** below the limit, it will exceed the limit rather than generate |
|
** an [SQLITE_NOMEM] error. In other words, the soft heap limit |
|
** is advisory only. |
|
** |
|
** ^The return value from sqlite3_soft_heap_limit64() is the size of |
|
** the soft heap limit prior to the call, or negative in the case of an |
|
** error. ^If the argument N is negative |
|
** then no change is made to the soft heap limit. Hence, the current |
|
** size of the soft heap limit can be determined by invoking |
|
** sqlite3_soft_heap_limit64() with a negative argument. |
|
** |
|
** ^If the argument N is zero then the soft heap limit is disabled. |
|
** |
|
** ^(The soft heap limit is not enforced in the current implementation |
|
** if one or more of following conditions are true: |
|
** |
|
** <ul> |
|
** <li> The soft heap limit is set to zero. |
|
** <li> Memory accounting is disabled using a combination of the |
|
** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and |
|
** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option. |
|
** <li> An alternative page cache implementation is specified using |
|
** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...). |
|
** <li> The page cache allocates from its own memory pool supplied |
|
** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than |
|
** from the heap. |
|
** </ul>)^ |
|
** |
|
** Beginning with SQLite [version 3.7.3] ([dateof:3.7.3]), |
|
** the soft heap limit is enforced |
|
** regardless of whether or not the [SQLITE_ENABLE_MEMORY_MANAGEMENT] |
|
** compile-time option is invoked. With [SQLITE_ENABLE_MEMORY_MANAGEMENT], |
|
** the soft heap limit is enforced on every memory allocation. Without |
|
** [SQLITE_ENABLE_MEMORY_MANAGEMENT], the soft heap limit is only enforced |
|
** when memory is allocated by the page cache. Testing suggests that because |
|
** the page cache is the predominate memory user in SQLite, most |
|
** applications will achieve adequate soft heap limit enforcement without |
|
** the use of [SQLITE_ENABLE_MEMORY_MANAGEMENT]. |
|
** |
|
** The circumstances under which SQLite will enforce the soft heap limit may |
|
** changes in future releases of SQLite. |
|
*/ |
|
SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N); |
|
|
|
/* |
|
** CAPI3REF: Deprecated Soft Heap Limit Interface |
|
** DEPRECATED |
|
** |
|
** This is a deprecated version of the [sqlite3_soft_heap_limit64()] |
|
** interface. This routine is provided for historical compatibility |
|
** only. All new applications should use the |
|
** [sqlite3_soft_heap_limit64()] interface rather than this one. |
|
*/ |
|
SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N); |
|
|
|
|
|
/* |
|
** CAPI3REF: Extract Metadata About A Column Of A Table |
|
** METHOD: sqlite3 |
|
** |
|
** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns |
|
** information about column C of table T in database D |
|
** on [database connection] X.)^ ^The sqlite3_table_column_metadata() |
|
** interface returns SQLITE_OK and fills in the non-NULL pointers in |
|
** the final five arguments with appropriate values if the specified |
|
** column exists. ^The sqlite3_table_column_metadata() interface returns |
|
** SQLITE_ERROR and if the specified column does not exist. |
|
** ^If the column-name parameter to sqlite3_table_column_metadata() is a |
|
** NULL pointer, then this routine simply checks for the existence of the |
|
** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it |
|
** does not. |
|
** |
|
** ^The column is identified by the second, third and fourth parameters to |
|
** this function. ^(The second parameter is either the name of the database |
|
** (i.e. "main", "temp", or an attached database) containing the specified |
|
** table or NULL.)^ ^If it is NULL, then all attached databases are searched |
|
** for the table using the same algorithm used by the database engine to |
|
** resolve unqualified table references. |
|
** |
|
** ^The third and fourth parameters to this function are the table and column |
|
** name of the desired column, respectively. |
|
** |
|
** ^Metadata is returned by writing to the memory locations passed as the 5th |
|
** and subsequent parameters to this function. ^Any of these arguments may be |
|
** NULL, in which case the corresponding element of metadata is omitted. |
|
** |
|
** ^(<blockquote> |
|
** <table border="1"> |
|
** <tr><th> Parameter <th> Output<br>Type <th> Description |
|
** |
|
** <tr><td> 5th <td> const char* <td> Data type |
|
** <tr><td> 6th <td> const char* <td> Name of default collation sequence |
|
** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint |
|
** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY |
|
** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT] |
|
** </table> |
|
** </blockquote>)^ |
|
** |
|
** ^The memory pointed to by the character pointers returned for the |
|
** declaration type and collation sequence is valid until the next |
|
** call to any SQLite API function. |
|
** |
|
** ^If the specified table is actually a view, an [error code] is returned. |
|
** |
|
** ^If the specified column is "rowid", "oid" or "_rowid_" and the table |
|
** is not a [WITHOUT ROWID] table and an |
|
** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output |
|
** parameters are set for the explicitly declared column. ^(If there is no |
|
** [INTEGER PRIMARY KEY] column, then the outputs |
|
** for the [rowid] are set as follows: |
|
** |
|
** <pre> |
|
** data type: "INTEGER" |
|
** collation sequence: "BINARY" |
|
** not null: 0 |
|
** primary key: 1 |
|
** auto increment: 0 |
|
** </pre>)^ |
|
** |
|
** ^This function causes all database schemas to be read from disk and |
|
** parsed, if that has not already been done, and returns an error if |
|
** any errors are encountered while loading the schema. |
|
*/ |
|
SQLITE_API int sqlite3_table_column_metadata( |
|
sqlite3 *db, /* Connection handle */ |
|
const char *zDbName, /* Database name or NULL */ |
|
const char *zTableName, /* Table name */ |
|
const char *zColumnName, /* Column name */ |
|
char const **pzDataType, /* OUTPUT: Declared data type */ |
|
char const **pzCollSeq, /* OUTPUT: Collation sequence name */ |
|
int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */ |
|
int *pPrimaryKey, /* OUTPUT: True if column part of PK */ |
|
int *pAutoinc /* OUTPUT: True if column is auto-increment */ |
|
); |
|
|
|
/* |
|
** CAPI3REF: Load An Extension |
|
** METHOD: sqlite3 |
|
** |
|
** ^This interface loads an SQLite extension library from the named file. |
|
** |
|
** ^The sqlite3_load_extension() interface attempts to load an |
|
** [SQLite extension] library contained in the file zFile. If |
|
** the file cannot be loaded directly, attempts are made to load |
|
** with various operating-system specific extensions added. |
|
** So for example, if "samplelib" cannot be loaded, then names like |
|
** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might |
|
** be tried also. |
|
** |
|
** ^The entry point is zProc. |
|
** ^(zProc may be 0, in which case SQLite will try to come up with an |
|
** entry point name on its own. It first tries "sqlite3_extension_init". |
|
** If that does not work, it constructs a name "sqlite3_X_init" where the |
|
** X is consists of the lower-case equivalent of all ASCII alphabetic |
|
** characters in the filename from the last "/" to the first following |
|
** "." and omitting any initial "lib".)^ |
|
** ^The sqlite3_load_extension() interface returns |
|
** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong. |
|
** ^If an error occurs and pzErrMsg is not 0, then the |
|
** [sqlite3_load_extension()] interface shall attempt to |
|
** fill *pzErrMsg with error message text stored in memory |
|
** obtained from [sqlite3_malloc()]. The calling function |
|
** should free this memory by calling [sqlite3_free()]. |
|
** |
|
** ^Extension loading must be enabled using |
|
** [sqlite3_enable_load_extension()] or |
|
** [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],1,NULL) |
|
** prior to calling this API, |
|
** otherwise an error will be returned. |
|
** |
|
** <b>Security warning:</b> It is recommended that the |
|
** [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method be used to enable only this |
|
** interface. The use of the [sqlite3_enable_load_extension()] interface |
|
** should be avoided. This will keep the SQL function [load_extension()] |
|
** disabled and prevent SQL injections from giving attackers |
|
** access to extension loading capabilities. |
|
** |
|
** See also the [load_extension() SQL function]. |
|
*/ |
|
SQLITE_API int sqlite3_load_extension( |
|
sqlite3 *db, /* Load the extension into this database connection */ |
|
const char *zFile, /* Name of the shared library containing extension */ |
|
const char *zProc, /* Entry point. Derived from zFile if 0 */ |
|
char **pzErrMsg /* Put error message here if not 0 */ |
|
); |
|
|
|
/* |
|
** CAPI3REF: Enable Or Disable Extension Loading |
|
** METHOD: sqlite3 |
|
** |
|
** ^So as not to open security holes in older applications that are |
|
** unprepared to deal with [extension loading], and as a means of disabling |
|
** [extension loading] while evaluating user-entered SQL, the following API |
|
** is provided to turn the [sqlite3_load_extension()] mechanism on and off. |
|
** |
|
** ^Extension loading is off by default. |
|
** ^Call the sqlite3_enable_load_extension() routine with onoff==1 |
|
** to turn extension loading on and call it with onoff==0 to turn |
|
** it back off again. |
|
** |
|
** ^This interface enables or disables both the C-API |
|
** [sqlite3_load_extension()] and the SQL function [load_extension()]. |
|
** ^(Use [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],..) |
|
** to enable or disable only the C-API.)^ |
|
** |
|
** <b>Security warning:</b> It is recommended that extension loading |
|
** be disabled using the [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method |
|
** rather than this interface, so the [load_extension()] SQL function |
|
** remains disabled. This will prevent SQL injections from giving attackers |
|
** access to extension loading capabilities. |
|
*/ |
|
SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff); |
|
|
|
/* |
|
** CAPI3REF: Automatically Load Statically Linked Extensions |
|
** |
|
** ^This interface causes the xEntryPoint() function to be invoked for |
|
** each new [database connection] that is created. The idea here is that |
|
** xEntryPoint() is the entry point for a statically linked [SQLite extension] |
|
** that is to be automatically loaded into all new database connections. |
|
** |
|
** ^(Even though the function prototype shows that xEntryPoint() takes |
|
** no arguments and returns void, SQLite invokes xEntryPoint() with three |
|
** arguments and expects an integer result as if the signature of the |
|
** entry point where as follows: |
|
** |
|
** <blockquote><pre> |
|
** int xEntryPoint( |
|
** sqlite3 *db, |
|
** const char **pzErrMsg, |
|
** const struct sqlite3_api_routines *pThunk |
|
** ); |
|
** </pre></blockquote>)^ |
|
** |
|
** If the xEntryPoint routine encounters an error, it should make *pzErrMsg |
|
** point to an appropriate error message (obtained from [sqlite3_mprintf()]) |
|
** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg |
|
** is NULL before calling the xEntryPoint(). ^SQLite will invoke |
|
** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any |
|
** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()], |
|
** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail. |
|
** |
|
** ^Calling sqlite3_auto_extension(X) with an entry point X that is already |
|
** on the list of automatic extensions is a harmless no-op. ^No entry point |
|
** will be called more than once for each database connection that is opened. |
|
** |
|
** See also: [sqlite3_reset_auto_extension()] |
|
** and [sqlite3_cancel_auto_extension()] |
|
*/ |
|
SQLITE_API int sqlite3_auto_extension(void(*xEntryPoint)(void)); |
|
|
|
/* |
|
** CAPI3REF: Cancel Automatic Extension Loading |
|
** |
|
** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the |
|
** initialization routine X that was registered using a prior call to |
|
** [sqlite3_auto_extension(X)]. ^The [sqlite3_cancel_auto_extension(X)] |
|
** routine returns 1 if initialization routine X was successfully |
|
** unregistered and it returns 0 if X was not on the list of initialization |
|
** routines. |
|
*/ |
|
SQLITE_API int sqlite3_cancel_auto_extension(void(*xEntryPoint)(void)); |
|
|
|
/* |
|
** CAPI3REF: Reset Automatic Extension Loading |
|
** |
|
** ^This interface disables all automatic extensions previously |
|
** registered using [sqlite3_auto_extension()]. |
|
*/ |
|
SQLITE_API void sqlite3_reset_auto_extension(void); |
|
|
|
/* |
|
** The interface to the virtual-table mechanism is currently considered |
|
** to be experimental. The interface might change in incompatible ways. |
|
** If this is a problem for you, do not use the interface at this time. |
|
** |
|
** When the virtual-table mechanism stabilizes, we will declare the |
|
** interface fixed, support it indefinitely, and remove this comment. |
|
*/ |
|
|
|
/* |
|
** Structures used by the virtual table interface |
|
*/ |
|
typedef struct sqlite3_vtab sqlite3_vtab; |
|
typedef struct sqlite3_index_info sqlite3_index_info; |
|
typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor; |
|
typedef struct sqlite3_module sqlite3_module; |
|
|
|
/* |
|
** CAPI3REF: Virtual Table Object |
|
** KEYWORDS: sqlite3_module {virtual table module} |
|
** |
|
** This structure, sometimes called a "virtual table module", |
|
** defines the implementation of a [virtual tables]. |
|
** This structure consists mostly of methods for the module. |
|
** |
|
** ^A virtual table module is created by filling in a persistent |
|
** instance of this structure and passing a pointer to that instance |
|
** to [sqlite3_create_module()] or [sqlite3_create_module_v2()]. |
|
** ^The registration remains valid until it is replaced by a different |
|
** module or until the [database connection] closes. The content |
|
** of this structure must not change while it is registered with |
|
** any database connection. |
|
*/ |
|
struct sqlite3_module { |
|
int iVersion; |
|
int (*xCreate)(sqlite3*, void *pAux, |
|
int argc, const char *const*argv, |
|
sqlite3_vtab **ppVTab, char**); |
|
int (*xConnect)(sqlite3*, void *pAux, |
|
int argc, const char *const*argv, |
|
sqlite3_vtab **ppVTab, char**); |
|
int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*); |
|
int (*xDisconnect)(sqlite3_vtab *pVTab); |
|
int (*xDestroy)(sqlite3_vtab *pVTab); |
|
int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor); |
|
int (*xClose)(sqlite3_vtab_cursor*); |
|
int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr, |
|
int argc, sqlite3_value **argv); |
|
int (*xNext)(sqlite3_vtab_cursor*); |
|
int (*xEof)(sqlite3_vtab_cursor*); |
|
int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int); |
|
int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid); |
|
int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *); |
|
int (*xBegin)(sqlite3_vtab *pVTab); |
|
int (*xSync)(sqlite3_vtab *pVTab); |
|
int (*xCommit)(sqlite3_vtab *pVTab); |
|
int (*xRollback)(sqlite3_vtab *pVTab); |
|
int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName, |
|
void (**pxFunc)(sqlite3_context*,int,sqlite3_value**), |
|
void **ppArg); |
|
int (*xRename)(sqlite3_vtab *pVtab, const char *zNew); |
|
/* The methods above are in version 1 of the sqlite_module object. Those |
|
** below are for version 2 and greater. */ |
|
int (*xSavepoint)(sqlite3_vtab *pVTab, int); |
|
int (*xRelease)(sqlite3_vtab *pVTab, int); |
|
int (*xRollbackTo)(sqlite3_vtab *pVTab, int); |
|
}; |
|
|
|
/* |
|
** CAPI3REF: Virtual Table Indexing Information |
|
** KEYWORDS: sqlite3_index_info |
|
** |
|
** The sqlite3_index_info structure and its substructures is used as part |
|
** of the [virtual table] interface to |
|
** pass information into and receive the reply from the [xBestIndex] |
|
** method of a [virtual table module]. The fields under **Inputs** are the |
|
** inputs to xBestIndex and are read-only. xBestIndex inserts its |
|
** results into the **Outputs** fields. |
|
** |
|
** ^(The aConstraint[] array records WHERE clause constraints of the form: |
|
** |
|
** <blockquote>column OP expr</blockquote> |
|
** |
|
** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is |
|
** stored in aConstraint[].op using one of the |
|
** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^ |
|
** ^(The index of the column is stored in |
|
** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the |
|
** expr on the right-hand side can be evaluated (and thus the constraint |
|
** is usable) and false if it cannot.)^ |
|
** |
|
** ^The optimizer automatically inverts terms of the form "expr OP column" |
|
** and makes other simplifications to the WHERE clause in an attempt to |
|
** get as many WHERE clause terms into the form shown above as possible. |
|
** ^The aConstraint[] array only reports WHERE clause terms that are |
|
** relevant to the particular virtual table being queried. |
|
** |
|
** ^Information about the ORDER BY clause is stored in aOrderBy[]. |
|
** ^Each term of aOrderBy records a column of the ORDER BY clause. |
|
** |
|
** The colUsed field indicates which columns of the virtual table may be |
|
** required by the current scan. Virtual table columns are numbered from |
|
** zero in the order in which they appear within the CREATE TABLE statement |
|
** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62), |
|
** the corresponding bit is set within the colUsed mask if the column may be |
|
** required by SQLite. If the table has at least 64 columns and any column |
|
** to the right of the first 63 is required, then bit 63 of colUsed is also |
|
** set. In other words, column iCol may be required if the expression |
|
** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to |
|
** non-zero. |
|
** |
|
** The [xBestIndex] method must fill aConstraintUsage[] with information |
|
** about what parameters to pass to xFilter. ^If argvIndex>0 then |
|
** the right-hand side of the corresponding aConstraint[] is evaluated |
|
** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit |
|
** is true, then the constraint is assumed to be fully handled by the |
|
** virtual table and is not checked again by SQLite.)^ |
|
** |
|
** ^The idxNum and idxPtr values are recorded and passed into the |
|
** [xFilter] method. |
|
** ^[sqlite3_free()] is used to free idxPtr if and only if |
|
** needToFreeIdxPtr is true. |
|
** |
|
** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in |
|
** the correct order to satisfy the ORDER BY clause so that no separate |
|
** sorting step is required. |
|
** |
|
** ^The estimatedCost value is an estimate of the cost of a particular |
|
** strategy. A cost of N indicates that the cost of the strategy is similar |
|
** to a linear scan of an SQLite table with N rows. A cost of log(N) |
|
** indicates that the expense of the operation is similar to that of a |
|
** binary search on a unique indexed field of an SQLite table with N rows. |
|
** |
|
** ^The estimatedRows value is an estimate of the number of rows that |
|
** will be returned by the strategy. |
|
** |
|
** The xBestIndex method may optionally populate the idxFlags field with a |
|
** mask of SQLITE_INDEX_SCAN_* flags. Currently there is only one such flag - |
|
** SQLITE_INDEX_SCAN_UNIQUE. If the xBestIndex method sets this flag, SQLite |
|
** assumes that the strategy may visit at most one row. |
|
** |
|
** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then |
|
** SQLite also assumes that if a call to the xUpdate() method is made as |
|
** part of the same statement to delete or update a virtual table row and the |
|
** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback |
|
** any database changes. In other words, if the xUpdate() returns |
|
** SQLITE_CONSTRAINT, the database contents must be exactly as they were |
|
** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not |
|
** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by |
|
** the xUpdate method are automatically rolled back by SQLite. |
|
** |
|
** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info |
|
** structure for SQLite [version 3.8.2] ([dateof:3.8.2]). |
|
** If a virtual table extension is |
|
** used with an SQLite version earlier than 3.8.2, the results of attempting |
|
** to read or write the estimatedRows field are undefined (but are likely |
|
** to included crashing the application). The estimatedRows field should |
|
** therefore only be used if [sqlite3_libversion_number()] returns a |
|
** value greater than or equal to 3008002. Similarly, the idxFlags field |
|
** was added for [version 3.9.0] ([dateof:3.9.0]). |
|
** It may therefore only be used if |
|
** sqlite3_libversion_number() returns a value greater than or equal to |
|
** 3009000. |
|
*/ |
|
struct sqlite3_index_info { |
|
/* Inputs */ |
|
int nConstraint; /* Number of entries in aConstraint */ |
|
struct sqlite3_index_constraint { |
|
int iColumn; /* Column constrained. -1 for ROWID */ |
|
unsigned char op; /* Constraint operator */ |
|
unsigned char usable; /* True if this constraint is usable */ |
|
int iTermOffset; /* Used internally - xBestIndex should ignore */ |
|
} *aConstraint; /* Table of WHERE clause constraints */ |
|
int nOrderBy; /* Number of terms in the ORDER BY clause */ |
|
struct sqlite3_index_orderby { |
|
int iColumn; /* Column number */ |
|
unsigned char desc; /* True for DESC. False for ASC. */ |
|
} *aOrderBy; /* The ORDER BY clause */ |
|
/* Outputs */ |
|
struct sqlite3_index_constraint_usage { |
|
int argvIndex; /* if >0, constraint is part of argv to xFilter */ |
|
unsigned char omit; /* Do not code a test for this constraint */ |
|
} *aConstraintUsage; |
|
int idxNum; /* Number used to identify the index */ |
|
char *idxStr; /* String, possibly obtained from sqlite3_malloc */ |
|
int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */ |
|
int orderByConsumed; /* True if output is already ordered */ |
|
double estimatedCost; /* Estimated cost of using this index */ |
|
/* Fields below are only available in SQLite 3.8.2 and later */ |
|
sqlite3_int64 estimatedRows; /* Estimated number of rows returned */ |
|
/* Fields below are only available in SQLite 3.9.0 and later */ |
|
int idxFlags; /* Mask of SQLITE_INDEX_SCAN_* flags */ |
|
/* Fields below are only available in SQLite 3.10.0 and later */ |
|
sqlite3_uint64 colUsed; /* Input: Mask of columns used by statement */ |
|
}; |
|
|
|
/* |
|
** CAPI3REF: Virtual Table Scan Flags |
|
*/ |
|
#define SQLITE_INDEX_SCAN_UNIQUE 1 /* Scan visits at most 1 row */ |
|
|
|
/* |
|
** CAPI3REF: Virtual Table Constraint Operator Codes |
|
** |
|
** These macros defined the allowed values for the |
|
** [sqlite3_index_info].aConstraint[].op field. Each value represents |
|
** an operator that is part of a constraint term in the wHERE clause of |
|
** a query that uses a [virtual table]. |
|
*/ |
|
#define SQLITE_INDEX_CONSTRAINT_EQ 2 |
|
#define SQLITE_INDEX_CONSTRAINT_GT 4 |
|
#define SQLITE_INDEX_CONSTRAINT_LE 8 |
|
#define SQLITE_INDEX_CONSTRAINT_LT 16 |
|
#define SQLITE_INDEX_CONSTRAINT_GE 32 |
|
#define SQLITE_INDEX_CONSTRAINT_MATCH 64 |
|
#define SQLITE_INDEX_CONSTRAINT_LIKE 65 |
|
#define SQLITE_INDEX_CONSTRAINT_GLOB 66 |
|
#define SQLITE_INDEX_CONSTRAINT_REGEXP 67 |
|
|
|
/* |
|
** CAPI3REF: Register A Virtual Table Implementation |
|
** METHOD: sqlite3 |
|
** |
|
** ^These routines are used to register a new [virtual table module] name. |
|
** ^Module names must be registered before |
|
** creating a new [virtual table] using the module and before using a |
|
** preexisting [virtual table] for the module. |
|
** |
|
** ^The module name is registered on the [database connection] specified |
|
** by the first parameter. ^The name of the module is given by the |
|
** second parameter. ^The third parameter is a pointer to |
|
** the implementation of the [virtual table module]. ^The fourth |
|
** parameter is an arbitrary client data pointer that is passed through |
|
** into the [xCreate] and [xConnect] methods of the virtual table module |
|
** when a new virtual table is be being created or reinitialized. |
|
** |
|
** ^The sqlite3_create_module_v2() interface has a fifth parameter which |
|
** is a pointer to a destructor for the pClientData. ^SQLite will |
|
** invoke the destructor function (if it is not NULL) when SQLite |
|
** no longer needs the pClientData pointer. ^The destructor will also |
|
** be invoked if the call to sqlite3_create_module_v2() fails. |
|
** ^The sqlite3_create_module() |
|
** interface is equivalent to sqlite3_create_module_v2() with a NULL |
|
** destructor. |
|
*/ |
|
SQLITE_API int sqlite3_create_module( |
|
sqlite3 *db, /* SQLite connection to register module with */ |
|
const char *zName, /* Name of the module */ |
|
const sqlite3_module *p, /* Methods for the module */ |
|
void *pClientData /* Client data for xCreate/xConnect */ |
|
); |
|
SQLITE_API int sqlite3_create_module_v2( |
|
sqlite3 *db, /* SQLite connection to register module with */ |
|
const char *zName, /* Name of the module */ |
|
const sqlite3_module *p, /* Methods for the module */ |
|
void *pClientData, /* Client data for xCreate/xConnect */ |
|
void(*xDestroy)(void*) /* Module destructor function */ |
|
); |
|
|
|
/* |
|
** CAPI3REF: Virtual Table Instance Object |
|
** KEYWORDS: sqlite3_vtab |
|
** |
|
** Every [virtual table module] implementation uses a subclass |
|
** of this object to describe a particular instance |
|
** of the [virtual table]. Each subclass will |
|
** be tailored to the specific needs of the module implementation. |
|
** The purpose of this superclass is to define certain fields that are |
|
** common to all module implementations. |
|
** |
|
** ^Virtual tables methods can set an error message by assigning a |
|
** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should |
|
** take care that any prior string is freed by a call to [sqlite3_free()] |
|
** prior to assigning a new string to zErrMsg. ^After the error message |
|
** is delivered up to the client application, the string will be automatically |
|
** freed by sqlite3_free() and the zErrMsg field will be zeroed. |
|
*/ |
|
struct sqlite3_vtab { |
|
const sqlite3_module *pModule; /* The module for this virtual table */ |
|
int nRef; /* Number of open cursors */ |
|
char *zErrMsg; /* Error message from sqlite3_mprintf() */ |
|
/* Virtual table implementations will typically add additional fields */ |
|
}; |
|
|
|
/* |
|
** CAPI3REF: Virtual Table Cursor Object |
|
** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor} |
|
** |
|
** Every [virtual table module] implementation uses a subclass of the |
|
** following structure to describe cursors that point into the |
|
** [virtual table] and are used |
|
** to loop through the virtual table. Cursors are created using the |
|
** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed |
|
** by the [sqlite3_module.xClose | xClose] method. Cursors are used |
|
** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods |
|
** of the module. Each module implementation will define |
|
** the content of a cursor structure to suit its own needs. |
|
** |
|
** This superclass exists in order to define fields of the cursor that |
|
** are common to all implementations. |
|
*/ |
|
struct sqlite3_vtab_cursor { |
|
sqlite3_vtab *pVtab; /* Virtual table of this cursor */ |
|
/* Virtual table implementations will typically add additional fields */ |
|
}; |
|
|
|
/* |
|
** CAPI3REF: Declare The Schema Of A Virtual Table |
|
** |
|
** ^The [xCreate] and [xConnect] methods of a |
|
** [virtual table module] call this interface |
|
** to declare the format (the names and datatypes of the columns) of |
|
** the virtual tables they implement. |
|
*/ |
|
SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL); |
|
|
|
/* |
|
** CAPI3REF: Overload A Function For A Virtual Table |
|
** METHOD: sqlite3 |
|
** |
|
** ^(Virtual tables can provide alternative implementations of functions |
|
** using the [xFindFunction] method of the [virtual table module]. |
|
** But global versions of those functions |
|
** must exist in order to be overloaded.)^ |
|
** |
|
** ^(This API makes sure a global version of a function with a particular |
|
** name and number of parameters exists. If no such function exists |
|
** before this API is called, a new function is created.)^ ^The implementation |
|
** of the new function always causes an exception to be thrown. So |
|
** the new function is not good for anything by itself. Its only |
|
** purpose is to be a placeholder function that can be overloaded |
|
** by a [virtual table]. |
|
*/ |
|
SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg); |
|
|
|
/* |
|
** The interface to the virtual-table mechanism defined above (back up |
|
** to a comment remarkably similar to this one) is currently considered |
|
** to be experimental. The interface might change in incompatible ways. |
|
** If this is a problem for you, do not use the interface at this time. |
|
** |
|
** When the virtual-table mechanism stabilizes, we will declare the |
|
** interface fixed, support it indefinitely, and remove this comment. |
|
*/ |
|
|
|
/* |
|
** CAPI3REF: A Handle To An Open BLOB |
|
** KEYWORDS: {BLOB handle} {BLOB handles} |
|
** |
|
** An instance of this object represents an open BLOB on which |
|
** [sqlite3_blob_open | incremental BLOB I/O] can be performed. |
|
** ^Objects of this type are created by [sqlite3_blob_open()] |
|
** and destroyed by [sqlite3_blob_close()]. |
|
** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces |
|
** can be used to read or write small subsections of the BLOB. |
|
** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes. |
|
*/ |
|
typedef struct sqlite3_blob sqlite3_blob; |
|
|
|
/* |
|
** CAPI3REF: Open A BLOB For Incremental I/O |
|
** METHOD: sqlite3 |
|
** CONSTRUCTOR: sqlite3_blob |
|
** |
|
** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located |
|
** in row iRow, column zColumn, table zTable in database zDb; |
|
** in other words, the same BLOB that would be selected by: |
|
** |
|
** <pre> |
|
** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow; |
|
** </pre>)^ |
|
** |
|
** ^(Parameter zDb is not the filename that contains the database, but |
|
** rather the symbolic name of the database. For attached databases, this is |
|
** the name that appears after the AS keyword in the [ATTACH] statement. |
|
** For the main database file, the database name is "main". For TEMP |
|
** tables, the database name is "temp".)^ |
|
** |
|
** ^If the flags parameter is non-zero, then the BLOB is opened for read |
|
** and write access. ^If the flags parameter is zero, the BLOB is opened for |
|
** read-only access. |
|
** |
|
** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored |
|
** in *ppBlob. Otherwise an [error code] is returned and, unless the error |
|
** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided |
|
** the API is not misused, it is always safe to call [sqlite3_blob_close()] |
|
** on *ppBlob after this function it returns. |
|
** |
|
** This function fails with SQLITE_ERROR if any of the following are true: |
|
** <ul> |
|
** <li> ^(Database zDb does not exist)^, |
|
** <li> ^(Table zTable does not exist within database zDb)^, |
|
** <li> ^(Table zTable is a WITHOUT ROWID table)^, |
|
** <li> ^(Column zColumn does not exist)^, |
|
** <li> ^(Row iRow is not present in the table)^, |
|
** <li> ^(The specified column of row iRow contains a value that is not |
|
** a TEXT or BLOB value)^, |
|
** <li> ^(Column zColumn is part of an index, PRIMARY KEY or UNIQUE |
|
** constraint and the blob is being opened for read/write access)^, |
|
** <li> ^([foreign key constraints | Foreign key constraints] are enabled, |
|
** column zColumn is part of a [child key] definition and the blob is |
|
** being opened for read/write access)^. |
|
** </ul> |
|
** |
|
** ^Unless it returns SQLITE_MISUSE, this function sets the |
|
** [database connection] error code and message accessible via |
|
** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. |
|
** |
|
** |
|
** ^(If the row that a BLOB handle points to is modified by an |
|
** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects |
|
** then the BLOB handle is marked as "expired". |
|
** This is true if any column of the row is changed, even a column |
|
** other than the one the BLOB handle is open on.)^ |
|
** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for |
|
** an expired BLOB handle fail with a return code of [SQLITE_ABORT]. |
|
** ^(Changes written into a BLOB prior to the BLOB expiring are not |
|
** rolled back by the expiration of the BLOB. Such changes will eventually |
|
** commit if the transaction continues to completion.)^ |
|
** |
|
** ^Use the [sqlite3_blob_bytes()] interface to determine the size of |
|
** the opened blob. ^The size of a blob may not be changed by this |
|
** interface. Use the [UPDATE] SQL command to change the size of a |
|
** blob. |
|
** |
|
** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces |
|
** and the built-in [zeroblob] SQL function may be used to create a |
|
** zero-filled blob to read or write using the incremental-blob interface. |
|
** |
|
** To avoid a resource leak, every open [BLOB handle] should eventually |
|
** be released by a call to [sqlite3_blob_close()]. |
|
*/ |
|
SQLITE_API int sqlite3_blob_open( |
|
sqlite3*, |
|
const char *zDb, |
|
const char *zTable, |
|
const char *zColumn, |
|
sqlite3_int64 iRow, |
|
int flags, |
|
sqlite3_blob **ppBlob |
|
); |
|
|
|
/* |
|
** CAPI3REF: Move a BLOB Handle to a New Row |
|
** METHOD: sqlite3_blob |
|
** |
|
** ^This function is used to move an existing blob handle so that it points |
|
** to a different row of the same database table. ^The new row is identified |
|
** by the rowid value passed as the second argument. Only the row can be |
|
** changed. ^The database, table and column on which the blob handle is open |
|
** remain the same. Moving an existing blob handle to a new row can be |
|
** faster than closing the existing handle and opening a new one. |
|
** |
|
** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] - |
|
** it must exist and there must be either a blob or text value stored in |
|
** the nominated column.)^ ^If the new row is not present in the table, or if |
|
** it does not contain a blob or text value, or if another error occurs, an |
|
** SQLite error code is returned and the blob handle is considered aborted. |
|
** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or |
|
** [sqlite3_blob_reopen()] on an aborted blob handle immediately return |
|
** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle |
|
** always returns zero. |
|
** |
|
** ^This function sets the database handle error code and message. |
|
*/ |
|
SQLITE_API int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64); |
|
|
|
/* |
|
** CAPI3REF: Close A BLOB Handle |
|
** DESTRUCTOR: sqlite3_blob |
|
** |
|
** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed |
|
** unconditionally. Even if this routine returns an error code, the |
|
** handle is still closed.)^ |
|
** |
|
** ^If the blob handle being closed was opened for read-write access, and if |
|
** the database is in auto-commit mode and there are no other open read-write |
|
** blob handles or active write statements, the current transaction is |
|
** committed. ^If an error occurs while committing the transaction, an error |
|
** code is returned and the transaction rolled back. |
|
** |
|
** Calling this function with an argument that is not a NULL pointer or an |
|
** open blob handle results in undefined behaviour. ^Calling this routine |
|
** with a null pointer (such as would be returned by a failed call to |
|
** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function |
|
** is passed a valid open blob handle, the values returned by the |
|
** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning. |
|
*/ |
|
SQLITE_API int sqlite3_blob_close(sqlite3_blob *); |
|
|
|
/* |
|
** CAPI3REF: Return The Size Of An Open BLOB |
|
** METHOD: sqlite3_blob |
|
** |
|
** ^Returns the size in bytes of the BLOB accessible via the |
|
** successfully opened [BLOB handle] in its only argument. ^The |
|
** incremental blob I/O routines can only read or overwriting existing |
|
** blob content; they cannot change the size of a blob. |
|
** |
|
** This routine only works on a [BLOB handle] which has been created |
|
** by a prior successful call to [sqlite3_blob_open()] and which has not |
|
** been closed by [sqlite3_blob_close()]. Passing any other pointer in |
|
** to this routine results in undefined and probably undesirable behavior. |
|
*/ |
|
SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *); |
|
|
|
/* |
|
** CAPI3REF: Read Data From A BLOB Incrementally |
|
** METHOD: sqlite3_blob |
|
** |
|
** ^(This function is used to read data from an open [BLOB handle] into a |
|
** caller-supplied buffer. N bytes of data are copied into buffer Z |
|
** from the open BLOB, starting at offset iOffset.)^ |
|
** |
|
** ^If offset iOffset is less than N bytes from the end of the BLOB, |
|
** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is |
|
** less than zero, [SQLITE_ERROR] is returned and no data is read. |
|
** ^The size of the blob (and hence the maximum value of N+iOffset) |
|
** can be determined using the [sqlite3_blob_bytes()] interface. |
|
** |
|
** ^An attempt to read from an expired [BLOB handle] fails with an |
|
** error code of [SQLITE_ABORT]. |
|
** |
|
** ^(On success, sqlite3_blob_read() returns SQLITE_OK. |
|
** Otherwise, an [error code] or an [extended error code] is returned.)^ |
|
** |
|
** This routine only works on a [BLOB handle] which has been created |
|
** by a prior successful call to [sqlite3_blob_open()] and which has not |
|
** been closed by [sqlite3_blob_close()]. Passing any other pointer in |
|
** to this routine results in undefined and probably undesirable behavior. |
|
** |
|
** See also: [sqlite3_blob_write()]. |
|
*/ |
|
SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset); |
|
|
|
/* |
|
** CAPI3REF: Write Data Into A BLOB Incrementally |
|
** METHOD: sqlite3_blob |
|
** |
|
** ^(This function is used to write data into an open [BLOB handle] from a |
|
** caller-supplied buffer. N bytes of data are copied from the buffer Z |
|
** into the open BLOB, starting at offset iOffset.)^ |
|
** |
|
** ^(On success, sqlite3_blob_write() returns SQLITE_OK. |
|
** Otherwise, an [error code] or an [extended error code] is returned.)^ |
|
** ^Unless SQLITE_MISUSE is returned, this function sets the |
|
** [database connection] error code and message accessible via |
|
** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. |
|
** |
|
** ^If the [BLOB handle] passed as the first argument was not opened for |
|
** writing (the flags parameter to [sqlite3_blob_open()] was zero), |
|
** this function returns [SQLITE_READONLY]. |
|
** |
|
** This function may only modify the contents of the BLOB; it is |
|
** not possible to increase the size of a BLOB using this API. |
|
** ^If offset iOffset is less than N bytes from the end of the BLOB, |
|
** [SQLITE_ERROR] is returned and no data is written. The size of the |
|
** BLOB (and hence the maximum value of N+iOffset) can be determined |
|
** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less |
|
** than zero [SQLITE_ERROR] is returned and no data is written. |
|
** |
|
** ^An attempt to write to an expired [BLOB handle] fails with an |
|
** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred |
|
** before the [BLOB handle] expired are not rolled back by the |
|
** expiration of the handle, though of course those changes might |
|
** have been overwritten by the statement that expired the BLOB handle |
|
** or by other independent statements. |
|
** |
|
** This routine only works on a [BLOB handle] which has been created |
|
** by a prior successful call to [sqlite3_blob_open()] and which has not |
|
** been closed by [sqlite3_blob_close()]. Passing any other pointer in |
|
** to this routine results in undefined and probably undesirable behavior. |
|
** |
|
** See also: [sqlite3_blob_read()]. |
|
*/ |
|
SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset); |
|
|
|
/* |
|
** CAPI3REF: Virtual File System Objects |
|
** |
|
** A virtual filesystem (VFS) is an [sqlite3_vfs] object |
|
** that SQLite uses to interact |
|
** with the underlying operating system. Most SQLite builds come with a |
|
** single default VFS that is appropriate for the host computer. |
|
** New VFSes can be registered and existing VFSes can be unregistered. |
|
** The following interfaces are provided. |
|
** |
|
** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name. |
|
** ^Names are case sensitive. |
|
** ^Names are zero-terminated UTF-8 strings. |
|
** ^If there is no match, a NULL pointer is returned. |
|
** ^If zVfsName is NULL then the default VFS is returned. |
|
** |
|
** ^New VFSes are registered with sqlite3_vfs_register(). |
|
** ^Each new VFS becomes the default VFS if the makeDflt flag is set. |
|
** ^The same VFS can be registered multiple times without injury. |
|
** ^To make an existing VFS into the default VFS, register it again |
|
** with the makeDflt flag set. If two different VFSes with the |
|
** same name are registered, the behavior is undefined. If a |
|
** VFS is registered with a name that is NULL or an empty string, |
|
** then the behavior is undefined. |
|
** |
|
** ^Unregister a VFS with the sqlite3_vfs_unregister() interface. |
|
** ^(If the default VFS is unregistered, another VFS is chosen as |
|
** the default. The choice for the new VFS is arbitrary.)^ |
|
*/ |
|
SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName); |
|
SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt); |
|
SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*); |
|
|
|
/* |
|
** CAPI3REF: Mutexes |
|
** |
|
** The SQLite core uses these routines for thread |
|
** synchronization. Though they are intended for internal |
|
** use by SQLite, code that links against SQLite is |
|
** permitted to use any of these routines. |
|
** |
|
** The SQLite source code contains multiple implementations |
|
** of these mutex routines. An appropriate implementation |
|
** is selected automatically at compile-time. The following |
|
** implementations are available in the SQLite core: |
|
** |
|
** <ul> |
|
** <li> SQLITE_MUTEX_PTHREADS |
|
** <li> SQLITE_MUTEX_W32 |
|
** <li> SQLITE_MUTEX_NOOP |
|
** </ul> |
|
** |
|
** The SQLITE_MUTEX_NOOP implementation is a set of routines |
|
** that does no real locking and is appropriate for use in |
|
** a single-threaded application. The SQLITE_MUTEX_PTHREADS and |
|
** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix |
|
** and Windows. |
|
** |
|
** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor |
|
** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex |
|
** implementation is included with the library. In this case the |
|
** application must supply a custom mutex implementation using the |
|
** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function |
|
** before calling sqlite3_initialize() or any other public sqlite3_ |
|
** function that calls sqlite3_initialize(). |
|
** |
|
** ^The sqlite3_mutex_alloc() routine allocates a new |
|
** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc() |
|
** routine returns NULL if it is unable to allocate the requested |
|
** mutex. The argument to sqlite3_mutex_alloc() must one of these |
|
** integer constants: |
|
** |
|
** <ul> |
|
** <li> SQLITE_MUTEX_FAST |
|
** <li> SQLITE_MUTEX_RECURSIVE |
|
** <li> SQLITE_MUTEX_STATIC_MASTER |
|
** <li> SQLITE_MUTEX_STATIC_MEM |
|
** <li> SQLITE_MUTEX_STATIC_OPEN |
|
** <li> SQLITE_MUTEX_STATIC_PRNG |
|
** <li> SQLITE_MUTEX_STATIC_LRU |
|
** <li> SQLITE_MUTEX_STATIC_PMEM |
|
** <li> SQLITE_MUTEX_STATIC_APP1 |
|
** <li> SQLITE_MUTEX_STATIC_APP2 |
|
** <li> SQLITE_MUTEX_STATIC_APP3 |
|
** <li> SQLITE_MUTEX_STATIC_VFS1 |
|
** <li> SQLITE_MUTEX_STATIC_VFS2 |
|
** <li> SQLITE_MUTEX_STATIC_VFS3 |
|
** </ul> |
|
** |
|
** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) |
|
** cause sqlite3_mutex_alloc() to create |
|
** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE |
|
** is used but not necessarily so when SQLITE_MUTEX_FAST is used. |
|
** The mutex implementation does not need to make a distinction |
|
** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does |
|
** not want to. SQLite will only request a recursive mutex in |
|
** cases where it really needs one. If a faster non-recursive mutex |
|
** implementation is available on the host platform, the mutex subsystem |
|
** might return such a mutex in response to SQLITE_MUTEX_FAST. |
|
** |
|
** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other |
|
** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return |
|
** a pointer to a static preexisting mutex. ^Nine static mutexes are |
|
** used by the current version of SQLite. Future versions of SQLite |
|
** may add additional static mutexes. Static mutexes are for internal |
|
** use by SQLite only. Applications that use SQLite mutexes should |
|
** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or |
|
** SQLITE_MUTEX_RECURSIVE. |
|
** |
|
** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST |
|
** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc() |
|
** returns a different mutex on every call. ^For the static |
|
** mutex types, the same mutex is returned on every call that has |
|
** the same type number. |
|
** |
|
** ^The sqlite3_mutex_free() routine deallocates a previously |
|
** allocated dynamic mutex. Attempting to deallocate a static |
|
** mutex results in undefined behavior. |
|
** |
|
** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt |
|
** to enter a mutex. ^If another thread is already within the mutex, |
|
** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return |
|
** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK] |
|
** upon successful entry. ^(Mutexes created using |
|
** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread. |
|
** In such cases, the |
|
** mutex must be exited an equal number of times before another thread |
|
** can enter.)^ If the same thread tries to enter any mutex other |
|
** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined. |
|
** |
|
** ^(Some systems (for example, Windows 95) do not support the operation |
|
** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try() |
|
** will always return SQLITE_BUSY. The SQLite core only ever uses |
|
** sqlite3_mutex_try() as an optimization so this is acceptable |
|
** behavior.)^ |
|
** |
|
** ^The sqlite3_mutex_leave() routine exits a mutex that was |
|
** previously entered by the same thread. The behavior |
|
** is undefined if the mutex is not currently entered by the |
|
** calling thread or is not currently allocated. |
|
** |
|
** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or |
|
** sqlite3_mutex_leave() is a NULL pointer, then all three routines |
|
** behave as no-ops. |
|
** |
|
** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()]. |
|
*/ |
|
SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int); |
|
SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*); |
|
SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*); |
|
SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*); |
|
SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*); |
|
|
|
/* |
|
** CAPI3REF: Mutex Methods Object |
|
** |
|
** An instance of this structure defines the low-level routines |
|
** used to allocate and use mutexes. |
|
** |
|
** Usually, the default mutex implementations provided by SQLite are |
|
** sufficient, however the application has the option of substituting a custom |
|
** implementation for specialized deployments or systems for which SQLite |
|
** does not provide a suitable implementation. In this case, the application |
|
** creates and populates an instance of this structure to pass |
|
** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option. |
|
** Additionally, an instance of this structure can be used as an |
|
** output variable when querying the system for the current mutex |
|
** implementation, using the [SQLITE_CONFIG_GETMUTEX] option. |
|
** |
|
** ^The xMutexInit method defined by this structure is invoked as |
|
** part of system initialization by the sqlite3_initialize() function. |
|
** ^The xMutexInit routine is called by SQLite exactly once for each |
|
** effective call to [sqlite3_initialize()]. |
|
** |
|
** ^The xMutexEnd method defined by this structure is invoked as |
|
** part of system shutdown by the sqlite3_shutdown() function. The |
|
** implementation of this method is expected to release all outstanding |
|
** resources obtained by the mutex methods implementation, especially |
|
** those obtained by the xMutexInit method. ^The xMutexEnd() |
|
** interface is invoked exactly once for each call to [sqlite3_shutdown()]. |
|
** |
|
** ^(The remaining seven methods defined by this structure (xMutexAlloc, |
|
** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and |
|
** xMutexNotheld) implement the following interfaces (respectively): |
|
** |
|
** <ul> |
|
** <li> [sqlite3_mutex_alloc()] </li> |
|
** <li> [sqlite3_mutex_free()] </li> |
|
** <li> [sqlite3_mutex_enter()] </li> |
|
** <li> [sqlite3_mutex_try()] </li> |
|
** <li> [sqlite3_mutex_leave()] </li> |
|
** <li> [sqlite3_mutex_held()] </li> |
|
** <li> [sqlite3_mutex_notheld()] </li> |
|
** </ul>)^ |
|
** |
|
** The only difference is that the public sqlite3_XXX functions enumerated |
|
** above silently ignore any invocations that pass a NULL pointer instead |
|
** of a valid mutex handle. The implementations of the methods defined |
|
** by this structure are not required to handle this case, the results |
|
** of passing a NULL pointer instead of a valid mutex handle are undefined |
|
** (i.e. it is acceptable to provide an implementation that segfaults if |
|
** it is passed a NULL pointer). |
|
** |
|
** The xMutexInit() method must be threadsafe. It must be harmless to |
|
** invoke xMutexInit() multiple times within the same process and without |
|
** intervening calls to xMutexEnd(). Second and subsequent calls to |
|
** xMutexInit() must be no-ops. |
|
** |
|
** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()] |
|
** and its associates). Similarly, xMutexAlloc() must not use SQLite memory |
|
** allocation for a static mutex. ^However xMutexAlloc() may use SQLite |
|
** memory allocation for a fast or recursive mutex. |
|
** |
|
** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is |
|
** called, but only if the prior call to xMutexInit returned SQLITE_OK. |
|
** If xMutexInit fails in any way, it is expected to clean up after itself |
|
** prior to returning. |
|
*/ |
|
typedef struct sqlite3_mutex_methods sqlite3_mutex_methods; |
|
struct sqlite3_mutex_methods { |
|
int (*xMutexInit)(void); |
|
int (*xMutexEnd)(void); |
|
sqlite3_mutex *(*xMutexAlloc)(int); |
|
void (*xMutexFree)(sqlite3_mutex *); |
|
void (*xMutexEnter)(sqlite3_mutex *); |
|
int (*xMutexTry)(sqlite3_mutex *); |
|
void (*xMutexLeave)(sqlite3_mutex *); |
|
int (*xMutexHeld)(sqlite3_mutex *); |
|
int (*xMutexNotheld)(sqlite3_mutex *); |
|
}; |
|
|
|
/* |
|
** CAPI3REF: Mutex Verification Routines |
|
** |
|
** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines |
|
** are intended for use inside assert() statements. The SQLite core |
|
** never uses these routines except inside an assert() and applications |
|
** are advised to follow the lead of the core. The SQLite core only |
|
** provides implementations for these routines when it is compiled |
|
** with the SQLITE_DEBUG flag. External mutex implementations |
|
** are only required to provide these routines if SQLITE_DEBUG is |
|
** defined and if NDEBUG is not defined. |
|
** |
|
** These routines should return true if the mutex in their argument |
|
** is held or not held, respectively, by the calling thread. |
|
** |
|
** The implementation is not required to provide versions of these |
|
** routines that actually work. If the implementation does not provide working |
|
** versions of these routines, it should at least provide stubs that always |
|
** return true so that one does not get spurious assertion failures. |
|
** |
|
** If the argument to sqlite3_mutex_held() is a NULL pointer then |
|
** the routine should return 1. This seems counter-intuitive since |
|
** clearly the mutex cannot be held if it does not exist. But |
|
** the reason the mutex does not exist is because the build is not |
|
** using mutexes. And we do not want the assert() containing the |
|
** call to sqlite3_mutex_held() to fail, so a non-zero return is |
|
** the appropriate thing to do. The sqlite3_mutex_notheld() |
|
** interface should also return 1 when given a NULL pointer. |
|
*/ |
|
#ifndef NDEBUG |
|
SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*); |
|
SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*); |
|
#endif |
|
|
|
/* |
|
** CAPI3REF: Mutex Types |
|
** |
|
** The [sqlite3_mutex_alloc()] interface takes a single argument |
|
** which is one of these integer constants. |
|
** |
|
** The set of static mutexes may change from one SQLite release to the |
|
** next. Applications that override the built-in mutex logic must be |
|
** prepared to accommodate additional static mutexes. |
|
*/ |
|
#define SQLITE_MUTEX_FAST 0 |
|
#define SQLITE_MUTEX_RECURSIVE 1 |
|
#define SQLITE_MUTEX_STATIC_MASTER 2 |
|
#define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */ |
|
#define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */ |
|
#define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */ |
|
#define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_randomness() */ |
|
#define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */ |
|
#define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */ |
|
#define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */ |
|
#define SQLITE_MUTEX_STATIC_APP1 8 /* For use by application */ |
|
#define SQLITE_MUTEX_STATIC_APP2 9 /* For use by application */ |
|
#define SQLITE_MUTEX_STATIC_APP3 10 /* For use by application */ |
|
#define SQLITE_MUTEX_STATIC_VFS1 11 /* For use by built-in VFS */ |
|
#define SQLITE_MUTEX_STATIC_VFS2 12 /* For use by extension VFS */ |
|
#define SQLITE_MUTEX_STATIC_VFS3 13 /* For use by application VFS */ |
|
|
|
/* |
|
** CAPI3REF: Retrieve the mutex for a database connection |
|
** METHOD: sqlite3 |
|
** |
|
** ^This interface returns a pointer the [sqlite3_mutex] object that |
|
** serializes access to the [database connection] given in the argument |
|
** when the [threading mode] is Serialized. |
|
** ^If the [threading mode] is Single-thread or Multi-thread then this |
|
** routine returns a NULL pointer. |
|
*/ |
|
SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*); |
|
|
|
/* |
|
** CAPI3REF: Low-Level Control Of Database Files |
|
** METHOD: sqlite3 |
|
** |
|
** ^The [sqlite3_file_control()] interface makes a direct call to the |
|
** xFileControl method for the [sqlite3_io_methods] object associated |
|
** with a particular database identified by the second argument. ^The |
|
** name of the database is "main" for the main database or "temp" for the |
|
** TEMP database, or the name that appears after the AS keyword for |
|
** databases that are added using the [ATTACH] SQL command. |
|
** ^A NULL pointer can be used in place of "main" to refer to the |
|
** main database file. |
|
** ^The third and fourth parameters to this routine |
|
** are passed directly through to the second and third parameters of |
|
** the xFileControl method. ^The return value of the xFileControl |
|
** method becomes the return value of this routine. |
|
** |
|
** ^The SQLITE_FCNTL_FILE_POINTER value for the op parameter causes |
|
** a pointer to the underlying [sqlite3_file] object to be written into |
|
** the space pointed to by the 4th parameter. ^The SQLITE_FCNTL_FILE_POINTER |
|
** case is a short-circuit path which does not actually invoke the |
|
** underlying sqlite3_io_methods.xFileControl method. |
|
** |
|
** ^If the second parameter (zDbName) does not match the name of any |
|
** open database file, then SQLITE_ERROR is returned. ^This error |
|
** code is not remembered and will not be recalled by [sqlite3_errcode()] |
|
** or [sqlite3_errmsg()]. The underlying xFileControl method might |
|
** also return SQLITE_ERROR. There is no way to distinguish between |
|
** an incorrect zDbName and an SQLITE_ERROR return from the underlying |
|
** xFileControl method. |
|
** |
|
** See also: [SQLITE_FCNTL_LOCKSTATE] |
|
*/ |
|
SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*); |
|
|
|
/* |
|
** CAPI3REF: Testing Interface |
|
** |
|
** ^The sqlite3_test_control() interface is used to read out internal |
|
** state of SQLite and to inject faults into SQLite for testing |
|
** purposes. ^The first parameter is an operation code that determines |
|
** the number, meaning, and operation of all subsequent parameters. |
|
** |
|
** This interface is not for use by applications. It exists solely |
|
** for verifying the correct operation of the SQLite library. Depending |
|
** on how the SQLite library is compiled, this interface might not exist. |
|
** |
|
** The details of the operation codes, their meanings, the parameters |
|
** they take, and what they do are all subject to change without notice. |
|
** Unlike most of the SQLite API, this function is not guaranteed to |
|
** operate consistently from one release to the next. |
|
*/ |
|
SQLITE_API int sqlite3_test_control(int op, ...); |
|
|
|
/* |
|
** CAPI3REF: Testing Interface Operation Codes |
|
** |
|
** These constants are the valid operation code parameters used |
|
** as the first argument to [sqlite3_test_control()]. |
|
** |
|
** These parameters and their meanings are subject to change |
|
** without notice. These values are for testing purposes only. |
|
** Applications should not use any of these parameters or the |
|
** [sqlite3_test_control()] interface. |
|
*/ |
|
#define SQLITE_TESTCTRL_FIRST 5 |
|
#define SQLITE_TESTCTRL_PRNG_SAVE 5 |
|
#define SQLITE_TESTCTRL_PRNG_RESTORE 6 |
|
#define SQLITE_TESTCTRL_PRNG_RESET 7 |
|
#define SQLITE_TESTCTRL_BITVEC_TEST 8 |
|
#define SQLITE_TESTCTRL_FAULT_INSTALL 9 |
|
#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10 |
|
#define SQLITE_TESTCTRL_PENDING_BYTE 11 |
|
#define SQLITE_TESTCTRL_ASSERT 12 |
|
#define SQLITE_TESTCTRL_ALWAYS 13 |
|
#define SQLITE_TESTCTRL_RESERVE 14 |
|
#define SQLITE_TESTCTRL_OPTIMIZATIONS 15 |
|
#define SQLITE_TESTCTRL_ISKEYWORD 16 |
|
#define SQLITE_TESTCTRL_SCRATCHMALLOC 17 |
|
#define SQLITE_TESTCTRL_LOCALTIME_FAULT 18 |
|
#define SQLITE_TESTCTRL_EXPLAIN_STMT 19 /* NOT USED */ |
|
#define SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD 19 |
|
#define SQLITE_TESTCTRL_NEVER_CORRUPT 20 |
|
#define SQLITE_TESTCTRL_VDBE_COVERAGE 21 |
|
#define SQLITE_TESTCTRL_BYTEORDER 22 |
|
#define SQLITE_TESTCTRL_ISINIT 23 |
|
#define SQLITE_TESTCTRL_SORTER_MMAP 24 |
|
#define SQLITE_TESTCTRL_IMPOSTER 25 |
|
#define SQLITE_TESTCTRL_LAST 25 |
|
|
|
/* |
|
** CAPI3REF: SQLite Runtime Status |
|
** |
|
** ^These interfaces are used to retrieve runtime status information |
|
** about the performance of SQLite, and optionally to reset various |
|
** highwater marks. ^The first argument is an integer code for |
|
** the specific parameter to measure. ^(Recognized integer codes |
|
** are of the form [status parameters | SQLITE_STATUS_...].)^ |
|
** ^The current value of the parameter is returned into *pCurrent. |
|
** ^The highest recorded value is returned in *pHighwater. ^If the |
|
** resetFlag is true, then the highest record value is reset after |
|
** *pHighwater is written. ^(Some parameters do not record the highest |
|
** value. For those parameters |
|
** nothing is written into *pHighwater and the resetFlag is ignored.)^ |
|
** ^(Other parameters record only the highwater mark and not the current |
|
** value. For these latter parameters nothing is written into *pCurrent.)^ |
|
** |
|
** ^The sqlite3_status() and sqlite3_status64() routines return |
|
** SQLITE_OK on success and a non-zero [error code] on failure. |
|
** |
|
** If either the current value or the highwater mark is too large to |
|
** be represented by a 32-bit integer, then the values returned by |
|
** sqlite3_status() are undefined. |
|
** |
|
** See also: [sqlite3_db_status()] |
|
*/ |
|
SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag); |
|
SQLITE_API int sqlite3_status64( |
|
int op, |
|
sqlite3_int64 *pCurrent, |
|
sqlite3_int64 *pHighwater, |
|
int resetFlag |
|
); |
|
|
|
|
|
/* |
|
** CAPI3REF: Status Parameters |
|
** KEYWORDS: {status parameters} |
|
** |
|
** These integer constants designate various run-time status parameters |
|
** that can be returned by [sqlite3_status()]. |
|
** |
|
** <dl> |
|
** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt> |
|
** <dd>This parameter is the current amount of memory checked out |
|
** using [sqlite3_malloc()], either directly or indirectly. The |
|
** figure includes calls made to [sqlite3_malloc()] by the application |
|
** and internal memory usage by the SQLite library. Scratch memory |
|
** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache |
|
** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in |
|
** this parameter. The amount returned is the sum of the allocation |
|
** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^ |
|
** |
|
** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt> |
|
** <dd>This parameter records the largest memory allocation request |
|
** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their |
|
** internal equivalents). Only the value returned in the |
|
** *pHighwater parameter to [sqlite3_status()] is of interest. |
|
** The value written into the *pCurrent parameter is undefined.</dd>)^ |
|
** |
|
** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt> |
|
** <dd>This parameter records the number of separate memory allocations |
|
** currently checked out.</dd>)^ |
|
** |
|
** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt> |
|
** <dd>This parameter returns the number of pages used out of the |
|
** [pagecache memory allocator] that was configured using |
|
** [SQLITE_CONFIG_PAGECACHE]. The |
|
** value returned is in pages, not in bytes.</dd>)^ |
|
** |
|
** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]] |
|
** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt> |
|
** <dd>This parameter returns the number of bytes of page cache |
|
** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE] |
|
** buffer and where forced to overflow to [sqlite3_malloc()]. The |
|
** returned value includes allocations that overflowed because they |
|
** where too large (they were larger than the "sz" parameter to |
|
** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because |
|
** no space was left in the page cache.</dd>)^ |
|
** |
|
** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt> |
|
** <dd>This parameter records the largest memory allocation request |
|
** handed to [pagecache memory allocator]. Only the value returned in the |
|
** *pHighwater parameter to [sqlite3_status()] is of interest. |
|
** The value written into the *pCurrent parameter is undefined.</dd>)^ |
|
** |
|
** [[SQLITE_STATUS_SCRATCH_USED]] ^(<dt>SQLITE_STATUS_SCRATCH_USED</dt> |
|
** <dd>This parameter returns the number of allocations used out of the |
|
** [scratch memory allocator] configured using |
|
** [SQLITE_CONFIG_SCRATCH]. The value returned is in allocations, not |
|
** in bytes. Since a single thread may only have one scratch allocation |
|
** outstanding at time, this parameter also reports the number of threads |
|
** using scratch memory at the same time.</dd>)^ |
|
** |
|
** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt> |
|
** <dd>This parameter returns the number of bytes of scratch memory |
|
** allocation which could not be satisfied by the [SQLITE_CONFIG_SCRATCH] |
|
** buffer and where forced to overflow to [sqlite3_malloc()]. The values |
|
** returned include overflows because the requested allocation was too |
|
** larger (that is, because the requested allocation was larger than the |
|
** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer |
|
** slots were available. |
|
** </dd>)^ |
|
** |
|
** [[SQLITE_STATUS_SCRATCH_SIZE]] ^(<dt>SQLITE_STATUS_SCRATCH_SIZE</dt> |
|
** <dd>This parameter records the largest memory allocation request |
|
** handed to [scratch memory allocator]. Only the value returned in the |
|
** *pHighwater parameter to [sqlite3_status()] is of interest. |
|
** The value written into the *pCurrent parameter is undefined.</dd>)^ |
|
** |
|
** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt> |
|
** <dd>The *pHighwater parameter records the deepest parser stack. |
|
** The *pCurrent value is undefined. The *pHighwater value is only |
|
** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^ |
|
** </dl> |
|
** |
|
** New status parameters may be added from time to time. |
|
*/ |
|
#define SQLITE_STATUS_MEMORY_USED 0 |
|
#define SQLITE_STATUS_PAGECACHE_USED 1 |
|
#define SQLITE_STATUS_PAGECACHE_OVERFLOW 2 |
|
#define SQLITE_STATUS_SCRATCH_USED 3 |
|
#define SQLITE_STATUS_SCRATCH_OVERFLOW 4 |
|
#define SQLITE_STATUS_MALLOC_SIZE 5 |
|
#define SQLITE_STATUS_PARSER_STACK 6 |
|
#define SQLITE_STATUS_PAGECACHE_SIZE 7 |
|
#define SQLITE_STATUS_SCRATCH_SIZE 8 |
|
#define SQLITE_STATUS_MALLOC_COUNT 9 |
|
|
|
/* |
|
** CAPI3REF: Database Connection Status |
|
** METHOD: sqlite3 |
|
** |
|
** ^This interface is used to retrieve runtime status information |
|
** about a single [database connection]. ^The first argument is the |
|
** database connection object to be interrogated. ^The second argument |
|
** is an integer constant, taken from the set of |
|
** [SQLITE_DBSTATUS options], that |
|
** determines the parameter to interrogate. The set of |
|
** [SQLITE_DBSTATUS options] is likely |
|
** to grow in future releases of SQLite. |
|
** |
|
** ^The current value of the requested parameter is written into *pCur |
|
** and the highest instantaneous value is written into *pHiwtr. ^If |
|
** the resetFlg is true, then the highest instantaneous value is |
|
** reset back down to the current value. |
|
** |
|
** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a |
|
** non-zero [error code] on failure. |
|
** |
|
** See also: [sqlite3_status()] and [sqlite3_stmt_status()]. |
|
*/ |
|
SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg); |
|
|
|
/* |
|
** CAPI3REF: Status Parameters for database connections |
|
** KEYWORDS: {SQLITE_DBSTATUS options} |
|
** |
|
** These constants are the available integer "verbs" that can be passed as |
|
** the second argument to the [sqlite3_db_status()] interface. |
|
** |
|
** New verbs may be added in future releases of SQLite. Existing verbs |
|
** might be discontinued. Applications should check the return code from |
|
** [sqlite3_db_status()] to make sure that the call worked. |
|
** The [sqlite3_db_status()] interface will return a non-zero error code |
|
** if a discontinued or unsupported verb is invoked. |
|
** |
|
** <dl> |
|
** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt> |
|
** <dd>This parameter returns the number of lookaside memory slots currently |
|
** checked out.</dd>)^ |
|
** |
|
** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt> |
|
** <dd>This parameter returns the number malloc attempts that were |
|
** satisfied using lookaside memory. Only the high-water value is meaningful; |
|
** the current value is always zero.)^ |
|
** |
|
** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]] |
|
** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt> |
|
** <dd>This parameter returns the number malloc attempts that might have |
|
** been satisfied using lookaside memory but failed due to the amount of |
|
** memory requested being larger than the lookaside slot size. |
|
** Only the high-water value is meaningful; |
|
** the current value is always zero.)^ |
|
** |
|
** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]] |
|
** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt> |
|
** <dd>This parameter returns the number malloc attempts that might have |
|
** been satisfied using lookaside memory but failed due to all lookaside |
|
** memory already being in use. |
|
** Only the high-water value is meaningful; |
|
** the current value is always zero.)^ |
|
** |
|
** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt> |
|
** <dd>This parameter returns the approximate number of bytes of heap |
|
** memory used by all pager caches associated with the database connection.)^ |
|
** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0. |
|
** |
|
** [[SQLITE_DBSTATUS_CACHE_USED_SHARED]] |
|
** ^(<dt>SQLITE_DBSTATUS_CACHE_USED_SHARED</dt> |
|
** <dd>This parameter is similar to DBSTATUS_CACHE_USED, except that if a |
|
** pager cache is shared between two or more connections the bytes of heap |
|
** memory used by that pager cache is divided evenly between the attached |
|
** connections.)^ In other words, if none of the pager caches associated |
|
** with the database connection are shared, this request returns the same |
|
** value as DBSTATUS_CACHE_USED. Or, if one or more or the pager caches are |
|
** shared, the value returned by this call will be smaller than that returned |
|
** by DBSTATUS_CACHE_USED. ^The highwater mark associated with |
|
** SQLITE_DBSTATUS_CACHE_USED_SHARED is always 0. |
|
** |
|
** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt> |
|
** <dd>This parameter returns the approximate number of bytes of heap |
|
** memory used to store the schema for all databases associated |
|
** with the connection - main, temp, and any [ATTACH]-ed databases.)^ |
|
** ^The full amount of memory used by the schemas is reported, even if the |
|
** schema memory is shared with other database connections due to |
|
** [shared cache mode] being enabled. |
|
** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0. |
|
** |
|
** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt> |
|
** <dd>This parameter returns the approximate number of bytes of heap |
|
** and lookaside memory used by all prepared statements associated with |
|
** the database connection.)^ |
|
** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0. |
|
** </dd> |
|
** |
|
** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt> |
|
** <dd>This parameter returns the number of pager cache hits that have |
|
** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT |
|
** is always 0. |
|
** </dd> |
|
** |
|
** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt> |
|
** <dd>This parameter returns the number of pager cache misses that have |
|
** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS |
|
** is always 0. |
|
** </dd> |
|
** |
|
** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(<dt>SQLITE_DBSTATUS_CACHE_WRITE</dt> |
|
** <dd>This parameter returns the number of dirty cache entries that have |
|
** been written to disk. Specifically, the number of pages written to the |
|
** wal file in wal mode databases, or the number of pages written to the |
|
** database file in rollback mode databases. Any pages written as part of |
|
** transaction rollback or database recovery operations are not included. |
|
** If an IO or other error occurs while writing a page to disk, the effect |
|
** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The |
|
** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0. |
|
** </dd> |
|
** |
|
** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt> |
|
** <dd>This parameter returns zero for the current value if and only if |
|
** all foreign key constraints (deferred or immediate) have been |
|
** resolved.)^ ^The highwater mark is always 0. |
|
** </dd> |
|
** </dl> |
|
*/ |
|
#define SQLITE_DBSTATUS_LOOKASIDE_USED 0 |
|
#define SQLITE_DBSTATUS_CACHE_USED 1 |
|
#define SQLITE_DBSTATUS_SCHEMA_USED 2 |
|
#define SQLITE_DBSTATUS_STMT_USED 3 |
|
#define SQLITE_DBSTATUS_LOOKASIDE_HIT 4 |
|
#define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE 5 |
|
#define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL 6 |
|
#define SQLITE_DBSTATUS_CACHE_HIT 7 |
|
#define SQLITE_DBSTATUS_CACHE_MISS 8 |
|
#define SQLITE_DBSTATUS_CACHE_WRITE 9 |
|
#define SQLITE_DBSTATUS_DEFERRED_FKS 10 |
|
#define SQLITE_DBSTATUS_CACHE_USED_SHARED 11 |
|
#define SQLITE_DBSTATUS_MAX 11 /* Largest defined DBSTATUS */ |
|
|
|
|
|
/* |
|
** CAPI3REF: Prepared Statement Status |
|
** METHOD: sqlite3_stmt |
|
** |
|
** ^(Each prepared statement maintains various |
|
** [SQLITE_STMTSTATUS counters] that measure the number |
|
** of times it has performed specific operations.)^ These counters can |
|
** be used to monitor the performance characteristics of the prepared |
|
** statements. For example, if the number of table steps greatly exceeds |
|
** the number of table searches or result rows, that would tend to indicate |
|
** that the prepared statement is using a full table scan rather than |
|
** an index. |
|
** |
|
** ^(This interface is used to retrieve and reset counter values from |
|
** a [prepared statement]. The first argument is the prepared statement |
|
** object to be interrogated. The second argument |
|
** is an integer code for a specific [SQLITE_STMTSTATUS counter] |
|
** to be interrogated.)^ |
|
** ^The current value of the requested counter is returned. |
|
** ^If the resetFlg is true, then the counter is reset to zero after this |
|
** interface call returns. |
|
** |
|
** See also: [sqlite3_status()] and [sqlite3_db_status()]. |
|
*/ |
|
SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg); |
|
|
|
/* |
|
** CAPI3REF: Status Parameters for prepared statements |
|
** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters} |
|
** |
|
** These preprocessor macros define integer codes that name counter |
|
** values associated with the [sqlite3_stmt_status()] interface. |
|
** The meanings of the various counters are as follows: |
|
** |
|
** <dl> |
|
** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt> |
|
** <dd>^This is the number of times that SQLite has stepped forward in |
|
** a table as part of a full table scan. Large numbers for this counter |
|
** may indicate opportunities for performance improvement through |
|
** careful use of indices.</dd> |
|
** |
|
** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt> |
|
** <dd>^This is the number of sort operations that have occurred. |
|
** A non-zero value in this counter may indicate an opportunity to |
|
** improvement performance through careful use of indices.</dd> |
|
** |
|
** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt> |
|
** <dd>^This is the number of rows inserted into transient indices that |
|
** were created automatically in order to help joins run faster. |
|
** A non-zero value in this counter may indicate an opportunity to |
|
** improvement performance by adding permanent indices that do not |
|
** need to be reinitialized each time the statement is run.</dd> |
|
** |
|
** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt> |
|
** <dd>^This is the number of virtual machine operations executed |
|
** by the prepared statement if that number is less than or equal |
|
** to 2147483647. The number of virtual machine operations can be |
|
** used as a proxy for the total work done by the prepared statement. |
|
** If the number of virtual machine operations exceeds 2147483647 |
|
** then the value returned by this statement status code is undefined. |
|
** </dd> |
|
** </dl> |
|
*/ |
|
#define SQLITE_STMTSTATUS_FULLSCAN_STEP 1 |
|
#define SQLITE_STMTSTATUS_SORT 2 |
|
#define SQLITE_STMTSTATUS_AUTOINDEX 3 |
|
#define SQLITE_STMTSTATUS_VM_STEP 4 |
|
|
|
/* |
|
** CAPI3REF: Custom Page Cache Object |
|
** |
|
** The sqlite3_pcache type is opaque. It is implemented by |
|
** the pluggable module. The SQLite core has no knowledge of |
|
** its size or internal structure and never deals with the |
|
** sqlite3_pcache object except by holding and passing pointers |
|
** to the object. |
|
** |
|
** See [sqlite3_pcache_methods2] for additional information. |
|
*/ |
|
typedef struct sqlite3_pcache sqlite3_pcache; |
|
|
|
/* |
|
** CAPI3REF: Custom Page Cache Object |
|
** |
|
** The sqlite3_pcache_page object represents a single page in the |
|
** page cache. The page cache will allocate instances of this |
|
** object. Various methods of the page cache use pointers to instances |
|
** of this object as parameters or as their return value. |
|
** |
|
** See [sqlite3_pcache_methods2] for additional information. |
|
*/ |
|
typedef struct sqlite3_pcache_page sqlite3_pcache_page; |
|
struct sqlite3_pcache_page { |
|
void *pBuf; /* The content of the page */ |
|
void *pExtra; /* Extra information associated with the page */ |
|
}; |
|
|
|
/* |
|
** CAPI3REF: Application Defined Page Cache. |
|
** KEYWORDS: {page cache} |
|
** |
|
** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can |
|
** register an alternative page cache implementation by passing in an |
|
** instance of the sqlite3_pcache_methods2 structure.)^ |
|
** In many applications, most of the heap memory allocated by |
|
** SQLite is used for the page cache. |
|
** By implementing a |
|
** custom page cache using this API, an application can better control |
|
** the amount of memory consumed by SQLite, the way in which |
|
** that memory is allocated and released, and the policies used to |
|
** determine exactly which parts of a database file are cached and for |
|
** how long. |
|
** |
|
** The alternative page cache mechanism is an |
|
** extreme measure that is only needed by the most demanding applications. |
|
** The built-in page cache is recommended for most uses. |
|
** |
|
** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an |
|
** internal buffer by SQLite within the call to [sqlite3_config]. Hence |
|
** the application may discard the parameter after the call to |
|
** [sqlite3_config()] returns.)^ |
|
** |
|
** [[the xInit() page cache method]] |
|
** ^(The xInit() method is called once for each effective |
|
** call to [sqlite3_initialize()])^ |
|
** (usually only once during the lifetime of the process). ^(The xInit() |
|
** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^ |
|
** The intent of the xInit() method is to set up global data structures |
|
** required by the custom page cache implementation. |
|
** ^(If the xInit() method is NULL, then the |
|
** built-in default page cache is used instead of the application defined |
|
** page cache.)^ |
|
** |
|
** [[the xShutdown() page cache method]] |
|
** ^The xShutdown() method is called by [sqlite3_shutdown()]. |
|
** It can be used to clean up |
|
** any outstanding resources before process shutdown, if required. |
|
** ^The xShutdown() method may be NULL. |
|
** |
|
** ^SQLite automatically serializes calls to the xInit method, |
|
** so the xInit method need not be threadsafe. ^The |
|
** xShutdown method is only called from [sqlite3_shutdown()] so it does |
|
** not need to be threadsafe either. All other methods must be threadsafe |
|
** in multithreaded applications. |
|
** |
|
** ^SQLite will never invoke xInit() more than once without an intervening |
|
** call to xShutdown(). |
|
** |
|
** [[the xCreate() page cache methods]] |
|
** ^SQLite invokes the xCreate() method to construct a new cache instance. |
|
** SQLite will typically create one cache instance for each open database file, |
|
** though this is not guaranteed. ^The |
|
** first parameter, szPage, is the size in bytes of the pages that must |
|
** be allocated by the cache. ^szPage will always a power of two. ^The |
|
** second parameter szExtra is a number of bytes of extra storage |
|
** associated with each page cache entry. ^The szExtra parameter will |
|
** a number less than 250. SQLite will use the |
|
** extra szExtra bytes on each page to store metadata about the underlying |
|
** database page on disk. The value passed into szExtra depends |
|
** on the SQLite version, the target platform, and how SQLite was compiled. |
|
** ^The third argument to xCreate(), bPurgeable, is true if the cache being |
|
** created will be used to cache database pages of a file stored on disk, or |
|
** false if it is used for an in-memory database. The cache implementation |
|
** does not have to do anything special based with the value of bPurgeable; |
|
** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will |
|
** never invoke xUnpin() except to deliberately delete a page. |
|
** ^In other words, calls to xUnpin() on a cache with bPurgeable set to |
|
** false will always have the "discard" flag set to true. |
|
** ^Hence, a cache created with bPurgeable false will |
|
** never contain any unpinned pages. |
|
** |
|
** [[the xCachesize() page cache method]] |
|
** ^(The xCachesize() method may be called at any time by SQLite to set the |
|
** suggested maximum cache-size (number of pages stored by) the cache |
|
** instance passed as the first argument. This is the value configured using |
|
** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable |
|
** parameter, the implementation is not required to do anything with this |
|
** value; it is advisory only. |
|
** |
|
** [[the xPagecount() page cache methods]] |
|
** The xPagecount() method must return the number of pages currently |
|
** stored in the cache, both pinned and unpinned. |
|
** |
|
** [[the xFetch() page cache methods]] |
|
** The xFetch() method locates a page in the cache and returns a pointer to |
|
** an sqlite3_pcache_page object associated with that page, or a NULL pointer. |
|
** The pBuf element of the returned sqlite3_pcache_page object will be a |
|
** pointer to a buffer of szPage bytes used to store the content of a |
|
** single database page. The pExtra element of sqlite3_pcache_page will be |
|
** a pointer to the szExtra bytes of extra storage that SQLite has requested |
|
** for each entry in the page cache. |
|
** |
|
** The page to be fetched is determined by the key. ^The minimum key value |
|
** is 1. After it has been retrieved using xFetch, the page is considered |
|
** to be "pinned". |
|
** |
|
** If the requested page is already in the page cache, then the page cache |
|
** implementation must return a pointer to the page buffer with its content |
|
** intact. If the requested page is not already in the cache, then the |
|
** cache implementation should use the value of the createFlag |
|
** parameter to help it determined what action to take: |
|
** |
|
** <table border=1 width=85% align=center> |
|
** <tr><th> createFlag <th> Behavior when page is not already in cache |
|
** <tr><td> 0 <td> Do not allocate a new page. Return NULL. |
|
** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so. |
|
** Otherwise return NULL. |
|
** <tr><td> 2 <td> Make every effort to allocate a new page. Only return |
|
** NULL if allocating a new page is effectively impossible. |
|
** </table> |
|
** |
|
** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite |
|
** will only use a createFlag of 2 after a prior call with a createFlag of 1 |
|
** failed.)^ In between the to xFetch() calls, SQLite may |
|
** attempt to unpin one or more cache pages by spilling the content of |
|
** pinned pages to disk and synching the operating system disk cache. |
|
** |
|
** [[the xUnpin() page cache method]] |
|
** ^xUnpin() is called by SQLite with a pointer to a currently pinned page |
|
** as its second argument. If the third parameter, discard, is non-zero, |
|
** then the page must be evicted from the cache. |
|
** ^If the discard parameter is |
|
** zero, then the page may be discarded or retained at the discretion of |
|
** page cache implementation. ^The page cache implementation |
|
** may choose to evict unpinned pages at any time. |
|
** |
|
** The cache must not perform any reference counting. A single |
|
** call to xUnpin() unpins the page regardless of the number of prior calls |
|
** to xFetch(). |
|
** |
|
** [[the xRekey() page cache methods]] |
|
** The xRekey() method is used to change the key value associated with the |
|
** page passed as the second argument. If the cache |
|
** previously contains an entry associated with newKey, it must be |
|
** discarded. ^Any prior cache entry associated with newKey is guaranteed not |
|
** to be pinned. |
|
** |
|
** When SQLite calls the xTruncate() method, the cache must discard all |
|
** existing cache entries with page numbers (keys) greater than or equal |
|
** to the value of the iLimit parameter passed to xTruncate(). If any |
|
** of these pages are pinned, they are implicitly unpinned, meaning that |
|
** they can be safely discarded. |
|
** |
|
** [[the xDestroy() page cache method]] |
|
** ^The xDestroy() method is used to delete a cache allocated by xCreate(). |
|
** All resources associated with the specified cache should be freed. ^After |
|
** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*] |
|
** handle invalid, and will not use it with any other sqlite3_pcache_methods2 |
|
** functions. |
|
** |
|
** [[the xShrink() page cache method]] |
|
** ^SQLite invokes the xShrink() method when it wants the page cache to |
|
** free up as much of heap memory as possible. The page cache implementation |
|
** is not obligated to free any memory, but well-behaved implementations should |
|
** do their best. |
|
*/ |
|
typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2; |
|
struct sqlite3_pcache_methods2 { |
|
int iVersion; |
|
void *pArg; |
|
int (*xInit)(void*); |
|
void (*xShutdown)(void*); |
|
sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable); |
|
void (*xCachesize)(sqlite3_pcache*, int nCachesize); |
|
int (*xPagecount)(sqlite3_pcache*); |
|
sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); |
|
void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard); |
|
void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*, |
|
unsigned oldKey, unsigned newKey); |
|
void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); |
|
void (*xDestroy)(sqlite3_pcache*); |
|
void (*xShrink)(sqlite3_pcache*); |
|
}; |
|
|
|
/* |
|
** This is the obsolete pcache_methods object that has now been replaced |
|
** by sqlite3_pcache_methods2. This object is not used by SQLite. It is |
|
** retained in the header file for backwards compatibility only. |
|
*/ |
|
typedef struct sqlite3_pcache_methods sqlite3_pcache_methods; |
|
struct sqlite3_pcache_methods { |
|
void *pArg; |
|
int (*xInit)(void*); |
|
void (*xShutdown)(void*); |
|
sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable); |
|
void (*xCachesize)(sqlite3_pcache*, int nCachesize); |
|
int (*xPagecount)(sqlite3_pcache*); |
|
void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); |
|
void (*xUnpin)(sqlite3_pcache*, void*, int discard); |
|
void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey); |
|
void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); |
|
void (*xDestroy)(sqlite3_pcache*); |
|
}; |
|
|
|
|
|
/* |
|
** CAPI3REF: Online Backup Object |
|
** |
|
** The sqlite3_backup object records state information about an ongoing |
|
** online backup operation. ^The sqlite3_backup object is created by |
|
** a call to [sqlite3_backup_init()] and is destroyed by a call to |
|
** [sqlite3_backup_finish()]. |
|
** |
|
** See Also: [Using the SQLite Online Backup API] |
|
*/ |
|
typedef struct sqlite3_backup sqlite3_backup; |
|
|
|
/* |
|
** CAPI3REF: Online Backup API. |
|
** |
|
** The backup API copies the content of one database into another. |
|
** It is useful either for creating backups of databases or |
|
** for copying in-memory databases to or from persistent files. |
|
** |
|
** See Also: [Using the SQLite Online Backup API] |
|
** |
|
** ^SQLite holds a write transaction open on the destination database file |
|
** for the duration of the backup operation. |
|
** ^The source database is read-locked only while it is being read; |
|
** it is not locked continuously for the entire backup operation. |
|
** ^Thus, the backup may be performed on a live source database without |
|
** preventing other database connections from |
|
** reading or writing to the source database while the backup is underway. |
|
** |
|
** ^(To perform a backup operation: |
|
** <ol> |
|
** <li><b>sqlite3_backup_init()</b> is called once to initialize the |
|
** backup, |
|
** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer |
|
** the data between the two databases, and finally |
|
** <li><b>sqlite3_backup_finish()</b> is called to release all resources |
|
** associated with the backup operation. |
|
** </ol>)^ |
|
** There should be exactly one call to sqlite3_backup_finish() for each |
|
** successful call to sqlite3_backup_init(). |
|
** |
|
** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b> |
|
** |
|
** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the |
|
** [database connection] associated with the destination database |
|
** and the database name, respectively. |
|
** ^The database name is "main" for the main database, "temp" for the |
|
** temporary database, or the name specified after the AS keyword in |
|
** an [ATTACH] statement for an attached database. |
|
** ^The S and M arguments passed to |
|
** sqlite3_backup_init(D,N,S,M) identify the [database connection] |
|
** and database name of the source database, respectively. |
|
** ^The source and destination [database connections] (parameters S and D) |
|
** must be different or else sqlite3_backup_init(D,N,S,M) will fail with |
|
** an error. |
|
** |
|
** ^A call to sqlite3_backup_init() will fail, returning NULL, if |
|
** there is already a read or read-write transaction open on the |
|
** destination database. |
|
** |
|
** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is |
|
** returned and an error code and error message are stored in the |
|
** destination [database connection] D. |
|
** ^The error code and message for the failed call to sqlite3_backup_init() |
|
** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or |
|
** [sqlite3_errmsg16()] functions. |
|
** ^A successful call to sqlite3_backup_init() returns a pointer to an |
|
** [sqlite3_backup] object. |
|
** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and |
|
** sqlite3_backup_finish() functions to perform the specified backup |
|
** operation. |
|
** |
|
** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b> |
|
** |
|
** ^Function sqlite3_backup_step(B,N) will copy up to N pages between |
|
** the source and destination databases specified by [sqlite3_backup] object B. |
|
** ^If N is negative, all remaining source pages are copied. |
|
** ^If sqlite3_backup_step(B,N) successfully copies N pages and there |
|
** are still more pages to be copied, then the function returns [SQLITE_OK]. |
|
** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages |
|
** from source to destination, then it returns [SQLITE_DONE]. |
|
** ^If an error occurs while running sqlite3_backup_step(B,N), |
|
** then an [error code] is returned. ^As well as [SQLITE_OK] and |
|
** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY], |
|
** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an |
|
** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code. |
|
** |
|
** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if |
|
** <ol> |
|
** <li> the destination database was opened read-only, or |
|
** <li> the destination database is using write-ahead-log journaling |
|
** and the destination and source page sizes differ, or |
|
** <li> the destination database is an in-memory database and the |
|
** destination and source page sizes differ. |
|
** </ol>)^ |
|
** |
|
** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then |
|
** the [sqlite3_busy_handler | busy-handler function] |
|
** is invoked (if one is specified). ^If the |
|
** busy-handler returns non-zero before the lock is available, then |
|
** [SQLITE_BUSY] is returned to the caller. ^In this case the call to |
|
** sqlite3_backup_step() can be retried later. ^If the source |
|
** [database connection] |
|
** is being used to write to the source database when sqlite3_backup_step() |
|
** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this |
|
** case the call to sqlite3_backup_step() can be retried later on. ^(If |
|
** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or |
|
** [SQLITE_READONLY] is returned, then |
|
** there is no point in retrying the call to sqlite3_backup_step(). These |
|
** errors are considered fatal.)^ The application must accept |
|
** that the backup operation has failed and pass the backup operation handle |
|
** to the sqlite3_backup_finish() to release associated resources. |
|
** |
|
** ^The first call to sqlite3_backup_step() obtains an exclusive lock |
|
** on the destination file. ^The exclusive lock is not released until either |
|
** sqlite3_backup_finish() is called or the backup operation is complete |
|
** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to |
|
** sqlite3_backup_step() obtains a [shared lock] on the source database that |
|
** lasts for the duration of the sqlite3_backup_step() call. |
|
** ^Because the source database is not locked between calls to |
|
** sqlite3_backup_step(), the source database may be modified mid-way |
|
** through the backup process. ^If the source database is modified by an |
|
** external process or via a database connection other than the one being |
|
** used by the backup operation, then the backup will be automatically |
|
** restarted by the next call to sqlite3_backup_step(). ^If the source |
|
** database is modified by the using the same database connection as is used |
|
** by the backup operation, then the backup database is automatically |
|
** updated at the same time. |
|
** |
|
** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b> |
|
** |
|
** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the |
|
** application wishes to abandon the backup operation, the application |
|
** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish(). |
|
** ^The sqlite3_backup_finish() interfaces releases all |
|
** resources associated with the [sqlite3_backup] object. |
|
** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any |
|
** active write-transaction on the destination database is rolled back. |
|
** The [sqlite3_backup] object is invalid |
|
** and may not be used following a call to sqlite3_backup_finish(). |
|
** |
|
** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no |
|
** sqlite3_backup_step() errors occurred, regardless or whether or not |
|
** sqlite3_backup_step() completed. |
|
** ^If an out-of-memory condition or IO error occurred during any prior |
|
** sqlite3_backup_step() call on the same [sqlite3_backup] object, then |
|
** sqlite3_backup_finish() returns the corresponding [error code]. |
|
** |
|
** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step() |
|
** is not a permanent error and does not affect the return value of |
|
** sqlite3_backup_finish(). |
|
** |
|
** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]] |
|
** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b> |
|
** |
|
** ^The sqlite3_backup_remaining() routine returns the number of pages still |
|
** to be backed up at the conclusion of the most recent sqlite3_backup_step(). |
|
** ^The sqlite3_backup_pagecount() routine returns the total number of pages |
|
** in the source database at the conclusion of the most recent |
|
** sqlite3_backup_step(). |
|
** ^(The values returned by these functions are only updated by |
|
** sqlite3_backup_step(). If the source database is modified in a way that |
|
** changes the size of the source database or the number of pages remaining, |
|
** those changes are not reflected in the output of sqlite3_backup_pagecount() |
|
** and sqlite3_backup_remaining() until after the next |
|
** sqlite3_backup_step().)^ |
|
** |
|
** <b>Concurrent Usage of Database Handles</b> |
|
** |
|
** ^The source [database connection] may be used by the application for other |
|
** purposes while a backup operation is underway or being initialized. |
|
** ^If SQLite is compiled and configured to support threadsafe database |
|
** connections, then the source database connection may be used concurrently |
|
** from within other threads. |
|
** |
|
** However, the application must guarantee that the destination |
|
** [database connection] is not passed to any other API (by any thread) after |
|
** sqlite3_backup_init() is called and before the corresponding call to |
|
** sqlite3_backup_finish(). SQLite does not currently check to see |
|
** if the application incorrectly accesses the destination [database connection] |
|
** and so no error code is reported, but the operations may malfunction |
|
** nevertheless. Use of the destination database connection while a |
|
** backup is in progress might also also cause a mutex deadlock. |
|
** |
|
** If running in [shared cache mode], the application must |
|
** guarantee that the shared cache used by the destination database |
|
** is not accessed while the backup is running. In practice this means |
|
** that the application must guarantee that the disk file being |
|
** backed up to is not accessed by any connection within the process, |
|
** not just the specific connection that was passed to sqlite3_backup_init(). |
|
** |
|
** The [sqlite3_backup] object itself is partially threadsafe. Multiple |
|
** threads may safely make multiple concurrent calls to sqlite3_backup_step(). |
|
** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount() |
|
** APIs are not strictly speaking threadsafe. If they are invoked at the |
|
** same time as another thread is invoking sqlite3_backup_step() it is |
|
** possible that they return invalid values. |
|
*/ |
|
SQLITE_API sqlite3_backup *sqlite3_backup_init( |
|
sqlite3 *pDest, /* Destination database handle */ |
|
const char *zDestName, /* Destination database name */ |
|
sqlite3 *pSource, /* Source database handle */ |
|
const char *zSourceName /* Source database name */ |
|
); |
|
SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage); |
|
SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p); |
|
SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p); |
|
SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p); |
|
|
|
/* |
|
** CAPI3REF: Unlock Notification |
|
** METHOD: sqlite3 |
|
** |
|
** ^When running in shared-cache mode, a database operation may fail with |
|
** an [SQLITE_LOCKED] error if the required locks on the shared-cache or |
|
** individual tables within the shared-cache cannot be obtained. See |
|
** [SQLite Shared-Cache Mode] for a description of shared-cache locking. |
|
** ^This API may be used to register a callback that SQLite will invoke |
|
** when the connection currently holding the required lock relinquishes it. |
|
** ^This API is only available if the library was compiled with the |
|
** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined. |
|
** |
|
** See Also: [Using the SQLite Unlock Notification Feature]. |
|
** |
|
** ^Shared-cache locks are released when a database connection concludes |
|
** its current transaction, either by committing it or rolling it back. |
|
** |
|
** ^When a connection (known as the blocked connection) fails to obtain a |
|
** shared-cache lock and SQLITE_LOCKED is returned to the caller, the |
|
** identity of the database connection (the blocking connection) that |
|
** has locked the required resource is stored internally. ^After an |
|
** application receives an SQLITE_LOCKED error, it may call the |
|
** sqlite3_unlock_notify() method with the blocked connection handle as |
|
** the first argument to register for a callback that will be invoked |
|
** when the blocking connections current transaction is concluded. ^The |
|
** callback is invoked from within the [sqlite3_step] or [sqlite3_close] |
|
** call that concludes the blocking connections transaction. |
|
** |
|
** ^(If sqlite3_unlock_notify() is called in a multi-threaded application, |
|
** there is a chance that the blocking connection will have already |
|
** concluded its transaction by the time sqlite3_unlock_notify() is invoked. |
|
** If this happens, then the specified callback is invoked immediately, |
|
** from within the call to sqlite3_unlock_notify().)^ |
|
** |
|
** ^If the blocked connection is attempting to obtain a write-lock on a |
|
** shared-cache table, and more than one other connection currently holds |
|
** a read-lock on the same table, then SQLite arbitrarily selects one of |
|
** the other connections to use as the blocking connection. |
|
** |
|
** ^(There may be at most one unlock-notify callback registered by a |
|
** blocked connection. If sqlite3_unlock_notify() is called when the |
|
** blocked connection already has a registered unlock-notify callback, |
|
** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is |
|
** called with a NULL pointer as its second argument, then any existing |
|
** unlock-notify callback is canceled. ^The blocked connections |
|
** unlock-notify callback may also be canceled by closing the blocked |
|
** connection using [sqlite3_close()]. |
|
** |
|
** The unlock-notify callback is not reentrant. If an application invokes |
|
** any sqlite3_xxx API functions from within an unlock-notify callback, a |
|
** crash or deadlock may be the result. |
|
** |
|
** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always |
|
** returns SQLITE_OK. |
|
** |
|
** <b>Callback Invocation Details</b> |
|
** |
|
** When an unlock-notify callback is registered, the application provides a |
|
** single void* pointer that is passed to the callback when it is invoked. |
|
** However, the signature of the callback function allows SQLite to pass |
|
** it an array of void* context pointers. The first argument passed to |
|
** an unlock-notify callback is a pointer to an array of void* pointers, |
|
** and the second is the number of entries in the array. |
|
** |
|
** When a blocking connections transaction is concluded, there may be |
|
** more than one blocked connection that has registered for an unlock-notify |
|
** callback. ^If two or more such blocked connections have specified the |
|
** same callback function, then instead of invoking the callback function |
|
** multiple times, it is invoked once with the set of void* context pointers |
|
** specified by the blocked connections bundled together into an array. |
|
** This gives the application an opportunity to prioritize any actions |
|
** related to the set of unblocked database connections. |
|
** |
|
** <b>Deadlock Detection</b> |
|
** |
|
** Assuming that after registering for an unlock-notify callback a |
|
** database waits for the callback to be issued before taking any further |
|
** action (a reasonable assumption), then using this API may cause the |
|
** application to deadlock. For example, if connection X is waiting for |
|
** connection Y's transaction to be concluded, and similarly connection |
|
** Y is waiting on connection X's transaction, then neither connection |
|
** will proceed and the system may remain deadlocked indefinitely. |
|
** |
|
** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock |
|
** detection. ^If a given call to sqlite3_unlock_notify() would put the |
|
** system in a deadlocked state, then SQLITE_LOCKED is returned and no |
|
** unlock-notify callback is registered. The system is said to be in |
|
** a deadlocked state if connection A has registered for an unlock-notify |
|
** callback on the conclusion of connection B's transaction, and connection |
|
** B has itself registered for an unlock-notify callback when connection |
|
** A's transaction is concluded. ^Indirect deadlock is also detected, so |
|
** the system is also considered to be deadlocked if connection B has |
|
** registered for an unlock-notify callback on the conclusion of connection |
|
** C's transaction, where connection C is waiting on connection A. ^Any |
|
** number of levels of indirection are allowed. |
|
** |
|
** <b>The "DROP TABLE" Exception</b> |
|
** |
|
** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost |
|
** always appropriate to call sqlite3_unlock_notify(). There is however, |
|
** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement, |
|
** SQLite checks if there are any currently executing SELECT statements |
|
** that belong to the same connection. If there are, SQLITE_LOCKED is |
|
** returned. In this case there is no "blocking connection", so invoking |
|
** sqlite3_unlock_notify() results in the unlock-notify callback being |
|
** invoked immediately. If the application then re-attempts the "DROP TABLE" |
|
** or "DROP INDEX" query, an infinite loop might be the result. |
|
** |
|
** One way around this problem is to check the extended error code returned |
|
** by an sqlite3_step() call. ^(If there is a blocking connection, then the |
|
** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in |
|
** the special "DROP TABLE/INDEX" case, the extended error code is just |
|
** SQLITE_LOCKED.)^ |
|
*/ |
|
SQLITE_API int sqlite3_unlock_notify( |
|
sqlite3 *pBlocked, /* Waiting connection */ |
|
void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */ |
|
void *pNotifyArg /* Argument to pass to xNotify */ |
|
); |
|
|
|
|
|
/* |
|
** CAPI3REF: String Comparison |
|
** |
|
** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications |
|
** and extensions to compare the contents of two buffers containing UTF-8 |
|
** strings in a case-independent fashion, using the same definition of "case |
|
** independence" that SQLite uses internally when comparing identifiers. |
|
*/ |
|
SQLITE_API int sqlite3_stricmp(const char *, const char *); |
|
SQLITE_API int sqlite3_strnicmp(const char *, const char *, int); |
|
|
|
/* |
|
** CAPI3REF: String Globbing |
|
* |
|
** ^The [sqlite3_strglob(P,X)] interface returns zero if and only if |
|
** string X matches the [GLOB] pattern P. |
|
** ^The definition of [GLOB] pattern matching used in |
|
** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the |
|
** SQL dialect understood by SQLite. ^The [sqlite3_strglob(P,X)] function |
|
** is case sensitive. |
|
** |
|
** Note that this routine returns zero on a match and non-zero if the strings |
|
** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()]. |
|
** |
|
** See also: [sqlite3_strlike()]. |
|
*/ |
|
SQLITE_API int sqlite3_strglob(const char *zGlob, const char *zStr); |
|
|
|
/* |
|
** CAPI3REF: String LIKE Matching |
|
* |
|
** ^The [sqlite3_strlike(P,X,E)] interface returns zero if and only if |
|
** string X matches the [LIKE] pattern P with escape character E. |
|
** ^The definition of [LIKE] pattern matching used in |
|
** [sqlite3_strlike(P,X,E)] is the same as for the "X LIKE P ESCAPE E" |
|
** operator in the SQL dialect understood by SQLite. ^For "X LIKE P" without |
|
** the ESCAPE clause, set the E parameter of [sqlite3_strlike(P,X,E)] to 0. |
|
** ^As with the LIKE operator, the [sqlite3_strlike(P,X,E)] function is case |
|
** insensitive - equivalent upper and lower case ASCII characters match |
|
** one another. |
|
** |
|
** ^The [sqlite3_strlike(P,X,E)] function matches Unicode characters, though |
|
** only ASCII characters are case folded. |
|
** |
|
** Note that this routine returns zero on a match and non-zero if the strings |
|
** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()]. |
|
** |
|
** See also: [sqlite3_strglob()]. |
|
*/ |
|
SQLITE_API int sqlite3_strlike(const char *zGlob, const char *zStr, unsigned int cEsc); |
|
|
|
/* |
|
** CAPI3REF: Error Logging Interface |
|
** |
|
** ^The [sqlite3_log()] interface writes a message into the [error log] |
|
** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()]. |
|
** ^If logging is enabled, the zFormat string and subsequent arguments are |
|
** used with [sqlite3_snprintf()] to generate the final output string. |
|
** |
|
** The sqlite3_log() interface is intended for use by extensions such as |
|
** virtual tables, collating functions, and SQL functions. While there is |
|
** nothing to prevent an application from calling sqlite3_log(), doing so |
|
** is considered bad form. |
|
** |
|
** The zFormat string must not be NULL. |
|
** |
|
** To avoid deadlocks and other threading problems, the sqlite3_log() routine |
|
** will not use dynamically allocated memory. The log message is stored in |
|
** a fixed-length buffer on the stack. If the log message is longer than |
|
** a few hundred characters, it will be truncated to the length of the |
|
** buffer. |
|
*/ |
|
SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...); |
|
|
|
/* |
|
** CAPI3REF: Write-Ahead Log Commit Hook |
|
** METHOD: sqlite3 |
|
** |
|
** ^The [sqlite3_wal_hook()] function is used to register a callback that |
|
** is invoked each time data is committed to a database in wal mode. |
|
** |
|
** ^(The callback is invoked by SQLite after the commit has taken place and |
|
** the associated write-lock on the database released)^, so the implementation |
|
** may read, write or [checkpoint] the database as required. |
|
** |
|
** ^The first parameter passed to the callback function when it is invoked |
|
** is a copy of the third parameter passed to sqlite3_wal_hook() when |
|
** registering the callback. ^The second is a copy of the database handle. |
|
** ^The third parameter is the name of the database that was written to - |
|
** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter |
|
** is the number of pages currently in the write-ahead log file, |
|
** including those that were just committed. |
|
** |
|
** The callback function should normally return [SQLITE_OK]. ^If an error |
|
** code is returned, that error will propagate back up through the |
|
** SQLite code base to cause the statement that provoked the callback |
|
** to report an error, though the commit will have still occurred. If the |
|
** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value |
|
** that does not correspond to any valid SQLite error code, the results |
|
** are undefined. |
|
** |
|
** A single database handle may have at most a single write-ahead log callback |
|
** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any |
|
** previously registered write-ahead log callback. ^Note that the |
|
** [sqlite3_wal_autocheckpoint()] interface and the |
|
** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will |
|
** overwrite any prior [sqlite3_wal_hook()] settings. |
|
*/ |
|
SQLITE_API void *sqlite3_wal_hook( |
|
sqlite3*, |
|
int(*)(void *,sqlite3*,const char*,int), |
|
void* |
|
); |
|
|
|
/* |
|
** CAPI3REF: Configure an auto-checkpoint |
|
** METHOD: sqlite3 |
|
** |
|
** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around |
|
** [sqlite3_wal_hook()] that causes any database on [database connection] D |
|
** to automatically [checkpoint] |
|
** after committing a transaction if there are N or |
|
** more frames in the [write-ahead log] file. ^Passing zero or |
|
** a negative value as the nFrame parameter disables automatic |
|
** checkpoints entirely. |
|
** |
|
** ^The callback registered by this function replaces any existing callback |
|
** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback |
|
** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism |
|
** configured by this function. |
|
** |
|
** ^The [wal_autocheckpoint pragma] can be used to invoke this interface |
|
** from SQL. |
|
** |
|
** ^Checkpoints initiated by this mechanism are |
|
** [sqlite3_wal_checkpoint_v2|PASSIVE]. |
|
** |
|
** ^Every new [database connection] defaults to having the auto-checkpoint |
|
** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT] |
|
** pages. The use of this interface |
|
** is only necessary if the default setting is found to be suboptimal |
|
** for a particular application. |
|
*/ |
|
SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N); |
|
|
|
/* |
|
** CAPI3REF: Checkpoint a database |
|
** METHOD: sqlite3 |
|
** |
|
** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to |
|
** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^ |
|
** |
|
** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the |
|
** [write-ahead log] for database X on [database connection] D to be |
|
** transferred into the database file and for the write-ahead log to |
|
** be reset. See the [checkpointing] documentation for addition |
|
** information. |
|
** |
|
** This interface used to be the only way to cause a checkpoint to |
|
** occur. But then the newer and more powerful [sqlite3_wal_checkpoint_v2()] |
|
** interface was added. This interface is retained for backwards |
|
** compatibility and as a convenience for applications that need to manually |
|
** start a callback but which do not need the full power (and corresponding |
|
** complication) of [sqlite3_wal_checkpoint_v2()]. |
|
*/ |
|
SQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb); |
|
|
|
/* |
|
** CAPI3REF: Checkpoint a database |
|
** METHOD: sqlite3 |
|
** |
|
** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint |
|
** operation on database X of [database connection] D in mode M. Status |
|
** information is written back into integers pointed to by L and C.)^ |
|
** ^(The M parameter must be a valid [checkpoint mode]:)^ |
|
** |
|
** <dl> |
|
** <dt>SQLITE_CHECKPOINT_PASSIVE<dd> |
|
** ^Checkpoint as many frames as possible without waiting for any database |
|
** readers or writers to finish, then sync the database file if all frames |
|
** in the log were checkpointed. ^The [busy-handler callback] |
|
** is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode. |
|
** ^On the other hand, passive mode might leave the checkpoint unfinished |
|
** if there are concurrent readers or writers. |
|
** |
|
** <dt>SQLITE_CHECKPOINT_FULL<dd> |
|
** ^This mode blocks (it invokes the |
|
** [sqlite3_busy_handler|busy-handler callback]) until there is no |
|
** database writer and all readers are reading from the most recent database |
|
** snapshot. ^It then checkpoints all frames in the log file and syncs the |
|
** database file. ^This mode blocks new database writers while it is pending, |
|
** but new database readers are allowed to continue unimpeded. |
|
** |
|
** <dt>SQLITE_CHECKPOINT_RESTART<dd> |
|
** ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition |
|
** that after checkpointing the log file it blocks (calls the |
|
** [busy-handler callback]) |
|
** until all readers are reading from the database file only. ^This ensures |
|
** that the next writer will restart the log file from the beginning. |
|
** ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new |
|
** database writer attempts while it is pending, but does not impede readers. |
|
** |
|
** <dt>SQLITE_CHECKPOINT_TRUNCATE<dd> |
|
** ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the |
|
** addition that it also truncates the log file to zero bytes just prior |
|
** to a successful return. |
|
** </dl> |
|
** |
|
** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in |
|
** the log file or to -1 if the checkpoint could not run because |
|
** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not |
|
** NULL,then *pnCkpt is set to the total number of checkpointed frames in the |
|
** log file (including any that were already checkpointed before the function |
|
** was called) or to -1 if the checkpoint could not run due to an error or |
|
** because the database is not in WAL mode. ^Note that upon successful |
|
** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been |
|
** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero. |
|
** |
|
** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If |
|
** any other process is running a checkpoint operation at the same time, the |
|
** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a |
|
** busy-handler configured, it will not be invoked in this case. |
|
** |
|
** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the |
|
** exclusive "writer" lock on the database file. ^If the writer lock cannot be |
|
** obtained immediately, and a busy-handler is configured, it is invoked and |
|
** the writer lock retried until either the busy-handler returns 0 or the lock |
|
** is successfully obtained. ^The busy-handler is also invoked while waiting for |
|
** database readers as described above. ^If the busy-handler returns 0 before |
|
** the writer lock is obtained or while waiting for database readers, the |
|
** checkpoint operation proceeds from that point in the same way as |
|
** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible |
|
** without blocking any further. ^SQLITE_BUSY is returned in this case. |
|
** |
|
** ^If parameter zDb is NULL or points to a zero length string, then the |
|
** specified operation is attempted on all WAL databases [attached] to |
|
** [database connection] db. In this case the |
|
** values written to output parameters *pnLog and *pnCkpt are undefined. ^If |
|
** an SQLITE_BUSY error is encountered when processing one or more of the |
|
** attached WAL databases, the operation is still attempted on any remaining |
|
** attached databases and SQLITE_BUSY is returned at the end. ^If any other |
|
** error occurs while processing an attached database, processing is abandoned |
|
** and the error code is returned to the caller immediately. ^If no error |
|
** (SQLITE_BUSY or otherwise) is encountered while processing the attached |
|
** databases, SQLITE_OK is returned. |
|
** |
|
** ^If database zDb is the name of an attached database that is not in WAL |
|
** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If |
|
** zDb is not NULL (or a zero length string) and is not the name of any |
|
** attached database, SQLITE_ERROR is returned to the caller. |
|
** |
|
** ^Unless it returns SQLITE_MISUSE, |
|
** the sqlite3_wal_checkpoint_v2() interface |
|
** sets the error information that is queried by |
|
** [sqlite3_errcode()] and [sqlite3_errmsg()]. |
|
** |
|
** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface |
|
** from SQL. |
|
*/ |
|
SQLITE_API int sqlite3_wal_checkpoint_v2( |
|
sqlite3 *db, /* Database handle */ |
|
const char *zDb, /* Name of attached database (or NULL) */ |
|
int eMode, /* SQLITE_CHECKPOINT_* value */ |
|
int *pnLog, /* OUT: Size of WAL log in frames */ |
|
int *pnCkpt /* OUT: Total number of frames checkpointed */ |
|
); |
|
|
|
/* |
|
** CAPI3REF: Checkpoint Mode Values |
|
** KEYWORDS: {checkpoint mode} |
|
** |
|
** These constants define all valid values for the "checkpoint mode" passed |
|
** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface. |
|
** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the |
|
** meaning of each of these checkpoint modes. |
|
*/ |
|
#define SQLITE_CHECKPOINT_PASSIVE 0 /* Do as much as possible w/o blocking */ |
|
#define SQLITE_CHECKPOINT_FULL 1 /* Wait for writers, then checkpoint */ |
|
#define SQLITE_CHECKPOINT_RESTART 2 /* Like FULL but wait for for readers */ |
|
#define SQLITE_CHECKPOINT_TRUNCATE 3 /* Like RESTART but also truncate WAL */ |
|
|
|
/* |
|
** CAPI3REF: Virtual Table Interface Configuration |
|
** |
|
** This function may be called by either the [xConnect] or [xCreate] method |
|
** of a [virtual table] implementation to configure |
|
** various facets of the virtual table interface. |
|
** |
|
** If this interface is invoked outside the context of an xConnect or |
|
** xCreate virtual table method then the behavior is undefined. |
|
** |
|
** At present, there is only one option that may be configured using |
|
** this function. (See [SQLITE_VTAB_CONSTRAINT_SUPPORT].) Further options |
|
** may be added in the future. |
|
*/ |
|
SQLITE_API int sqlite3_vtab_config(sqlite3*, int op, ...); |
|
|
|
/* |
|
** CAPI3REF: Virtual Table Configuration Options |
|
** |
|
** These macros define the various options to the |
|
** [sqlite3_vtab_config()] interface that [virtual table] implementations |
|
** can use to customize and optimize their behavior. |
|
** |
|
** <dl> |
|
** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT |
|
** <dd>Calls of the form |
|
** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported, |
|
** where X is an integer. If X is zero, then the [virtual table] whose |
|
** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not |
|
** support constraints. In this configuration (which is the default) if |
|
** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire |
|
** statement is rolled back as if [ON CONFLICT | OR ABORT] had been |
|
** specified as part of the users SQL statement, regardless of the actual |
|
** ON CONFLICT mode specified. |
|
** |
|
** If X is non-zero, then the virtual table implementation guarantees |
|
** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before |
|
** any modifications to internal or persistent data structures have been made. |
|
** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite |
|
** is able to roll back a statement or database transaction, and abandon |
|
** or continue processing the current SQL statement as appropriate. |
|
** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns |
|
** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode |
|
** had been ABORT. |
|
** |
|
** Virtual table implementations that are required to handle OR REPLACE |
|
** must do so within the [xUpdate] method. If a call to the |
|
** [sqlite3_vtab_on_conflict()] function indicates that the current ON |
|
** CONFLICT policy is REPLACE, the virtual table implementation should |
|
** silently replace the appropriate rows within the xUpdate callback and |
|
** return SQLITE_OK. Or, if this is not possible, it may return |
|
** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT |
|
** constraint handling. |
|
** </dl> |
|
*/ |
|
#define SQLITE_VTAB_CONSTRAINT_SUPPORT 1 |
|
|
|
/* |
|
** CAPI3REF: Determine The Virtual Table Conflict Policy |
|
** |
|
** This function may only be called from within a call to the [xUpdate] method |
|
** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The |
|
** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL], |
|
** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode |
|
** of the SQL statement that triggered the call to the [xUpdate] method of the |
|
** [virtual table]. |
|
*/ |
|
SQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *); |
|
|
|
/* |
|
** CAPI3REF: Conflict resolution modes |
|
** KEYWORDS: {conflict resolution mode} |
|
** |
|
** These constants are returned by [sqlite3_vtab_on_conflict()] to |
|
** inform a [virtual table] implementation what the [ON CONFLICT] mode |
|
** is for the SQL statement being evaluated. |
|
** |
|
** Note that the [SQLITE_IGNORE] constant is also used as a potential |
|
** return value from the [sqlite3_set_authorizer()] callback and that |
|
** [SQLITE_ABORT] is also a [result code]. |
|
*/ |
|
#define SQLITE_ROLLBACK 1 |
|
/* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */ |
|
#define SQLITE_FAIL 3 |
|
/* #define SQLITE_ABORT 4 // Also an error code */ |
|
#define SQLITE_REPLACE 5 |
|
|
|
/* |
|
** CAPI3REF: Prepared Statement Scan Status Opcodes |
|
** KEYWORDS: {scanstatus options} |
|
** |
|
** The following constants can be used for the T parameter to the |
|
** [sqlite3_stmt_scanstatus(S,X,T,V)] interface. Each constant designates a |
|
** different metric for sqlite3_stmt_scanstatus() to return. |
|
** |
|
** When the value returned to V is a string, space to hold that string is |
|
** managed by the prepared statement S and will be automatically freed when |
|
** S is finalized. |
|
** |
|
** <dl> |
|
** [[SQLITE_SCANSTAT_NLOOP]] <dt>SQLITE_SCANSTAT_NLOOP</dt> |
|
** <dd>^The [sqlite3_int64] variable pointed to by the T parameter will be |
|
** set to the total number of times that the X-th loop has run.</dd> |
|
** |
|
** [[SQLITE_SCANSTAT_NVISIT]] <dt>SQLITE_SCANSTAT_NVISIT</dt> |
|
** <dd>^The [sqlite3_int64] variable pointed to by the T parameter will be set |
|
** to the total number of rows examined by all iterations of the X-th loop.</dd> |
|
** |
|
** [[SQLITE_SCANSTAT_EST]] <dt>SQLITE_SCANSTAT_EST</dt> |
|
** <dd>^The "double" variable pointed to by the T parameter will be set to the |
|
** query planner's estimate for the average number of rows output from each |
|
** iteration of the X-th loop. If the query planner's estimates was accurate, |
|
** then this value will approximate the quotient NVISIT/NLOOP and the |
|
** product of this value for all prior loops with the same SELECTID will |
|
** be the NLOOP value for the current loop. |
|
** |
|
** [[SQLITE_SCANSTAT_NAME]] <dt>SQLITE_SCANSTAT_NAME</dt> |
|
** <dd>^The "const char *" variable pointed to by the T parameter will be set |
|
** to a zero-terminated UTF-8 string containing the name of the index or table |
|
** used for the X-th loop. |
|
** |
|
** [[SQLITE_SCANSTAT_EXPLAIN]] <dt>SQLITE_SCANSTAT_EXPLAIN</dt> |
|
** <dd>^The "const char *" variable pointed to by the T parameter will be set |
|
** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN] |
|
** description for the X-th loop. |
|
** |
|
** [[SQLITE_SCANSTAT_SELECTID]] <dt>SQLITE_SCANSTAT_SELECT</dt> |
|
** <dd>^The "int" variable pointed to by the T parameter will be set to the |
|
** "select-id" for the X-th loop. The select-id identifies which query or |
|
** subquery the loop is part of. The main query has a select-id of zero. |
|
** The select-id is the same value as is output in the first column |
|
** of an [EXPLAIN QUERY PLAN] query. |
|
** </dl> |
|
*/ |
|
#define SQLITE_SCANSTAT_NLOOP 0 |
|
#define SQLITE_SCANSTAT_NVISIT 1 |
|
#define SQLITE_SCANSTAT_EST 2 |
|
#define SQLITE_SCANSTAT_NAME 3 |
|
#define SQLITE_SCANSTAT_EXPLAIN 4 |
|
#define SQLITE_SCANSTAT_SELECTID 5 |
|
|
|
/* |
|
** CAPI3REF: Prepared Statement Scan Status |
|
** METHOD: sqlite3_stmt |
|
** |
|
** This interface returns information about the predicted and measured |
|
** performance for pStmt. Advanced applications can use this |
|
** interface to compare the predicted and the measured performance and |
|
** issue warnings and/or rerun [ANALYZE] if discrepancies are found. |
|
** |
|
** Since this interface is expected to be rarely used, it is only |
|
** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS] |
|
** compile-time option. |
|
** |
|
** The "iScanStatusOp" parameter determines which status information to return. |
|
** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior |
|
** of this interface is undefined. |
|
** ^The requested measurement is written into a variable pointed to by |
|
** the "pOut" parameter. |
|
** Parameter "idx" identifies the specific loop to retrieve statistics for. |
|
** Loops are numbered starting from zero. ^If idx is out of range - less than |
|
** zero or greater than or equal to the total number of loops used to implement |
|
** the statement - a non-zero value is returned and the variable that pOut |
|
** points to is unchanged. |
|
** |
|
** ^Statistics might not be available for all loops in all statements. ^In cases |
|
** where there exist loops with no available statistics, this function behaves |
|
** as if the loop did not exist - it returns non-zero and leave the variable |
|
** that pOut points to unchanged. |
|
** |
|
** See also: [sqlite3_stmt_scanstatus_reset()] |
|
*/ |
|
SQLITE_API int sqlite3_stmt_scanstatus( |
|
sqlite3_stmt *pStmt, /* Prepared statement for which info desired */ |
|
int idx, /* Index of loop to report on */ |
|
int iScanStatusOp, /* Information desired. SQLITE_SCANSTAT_* */ |
|
void *pOut /* Result written here */ |
|
); |
|
|
|
/* |
|
** CAPI3REF: Zero Scan-Status Counters |
|
** METHOD: sqlite3_stmt |
|
** |
|
** ^Zero all [sqlite3_stmt_scanstatus()] related event counters. |
|
** |
|
** This API is only available if the library is built with pre-processor |
|
** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined. |
|
*/ |
|
SQLITE_API void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*); |
|
|
|
/* |
|
** CAPI3REF: Flush caches to disk mid-transaction |
|
** |
|
** ^If a write-transaction is open on [database connection] D when the |
|
** [sqlite3_db_cacheflush(D)] interface invoked, any dirty |
|
** pages in the pager-cache that are not currently in use are written out |
|
** to disk. A dirty page may be in use if a database cursor created by an |
|
** active SQL statement is reading from it, or if it is page 1 of a database |
|
** file (page 1 is always "in use"). ^The [sqlite3_db_cacheflush(D)] |
|
** interface flushes caches for all schemas - "main", "temp", and |
|
** any [attached] databases. |
|
** |
|
** ^If this function needs to obtain extra database locks before dirty pages |
|
** can be flushed to disk, it does so. ^If those locks cannot be obtained |
|
** immediately and there is a busy-handler callback configured, it is invoked |
|
** in the usual manner. ^If the required lock still cannot be obtained, then |
|
** the database is skipped and an attempt made to flush any dirty pages |
|
** belonging to the next (if any) database. ^If any databases are skipped |
|
** because locks cannot be obtained, but no other error occurs, this |
|
** function returns SQLITE_BUSY. |
|
** |
|
** ^If any other error occurs while flushing dirty pages to disk (for |
|
** example an IO error or out-of-memory condition), then processing is |
|
** abandoned and an SQLite [error code] is returned to the caller immediately. |
|
** |
|
** ^Otherwise, if no error occurs, [sqlite3_db_cacheflush()] returns SQLITE_OK. |
|
** |
|
** ^This function does not set the database handle error code or message |
|
** returned by the [sqlite3_errcode()] and [sqlite3_errmsg()] functions. |
|
*/ |
|
SQLITE_API int sqlite3_db_cacheflush(sqlite3*); |
|
|
|
/* |
|
** CAPI3REF: The pre-update hook. |
|
** |
|
** ^These interfaces are only available if SQLite is compiled using the |
|
** [SQLITE_ENABLE_PREUPDATE_HOOK] compile-time option. |
|
** |
|
** ^The [sqlite3_preupdate_hook()] interface registers a callback function |
|
** that is invoked prior to each [INSERT], [UPDATE], and [DELETE] operation |
|
** on a [rowid table]. |
|
** ^At most one preupdate hook may be registered at a time on a single |
|
** [database connection]; each call to [sqlite3_preupdate_hook()] overrides |
|
** the previous setting. |
|
** ^The preupdate hook is disabled by invoking [sqlite3_preupdate_hook()] |
|
** with a NULL pointer as the second parameter. |
|
** ^The third parameter to [sqlite3_preupdate_hook()] is passed through as |
|
** the first parameter to callbacks. |
|
** |
|
** ^The preupdate hook only fires for changes to [rowid tables]; the preupdate |
|
** hook is not invoked for changes to [virtual tables] or [WITHOUT ROWID] |
|
** tables. |
|
** |
|
** ^The second parameter to the preupdate callback is a pointer to |
|
** the [database connection] that registered the preupdate hook. |
|
** ^The third parameter to the preupdate callback is one of the constants |
|
** [SQLITE_INSERT], [SQLITE_DELETE], or [SQLITE_UPDATE] to identify the |
|
** kind of update operation that is about to occur. |
|
** ^(The fourth parameter to the preupdate callback is the name of the |
|
** database within the database connection that is being modified. This |
|
** will be "main" for the main database or "temp" for TEMP tables or |
|
** the name given after the AS keyword in the [ATTACH] statement for attached |
|
** databases.)^ |
|
** ^The fifth parameter to the preupdate callback is the name of the |
|
** table that is being modified. |
|
** ^The sixth parameter to the preupdate callback is the initial [rowid] of the |
|
** row being changes for SQLITE_UPDATE and SQLITE_DELETE changes and is |
|
** undefined for SQLITE_INSERT changes. |
|
** ^The seventh parameter to the preupdate callback is the final [rowid] of |
|
** the row being changed for SQLITE_UPDATE and SQLITE_INSERT changes and is |
|
** undefined for SQLITE_DELETE changes. |
|
** |
|
** The [sqlite3_preupdate_old()], [sqlite3_preupdate_new()], |
|
** [sqlite3_preupdate_count()], and [sqlite3_preupdate_depth()] interfaces |
|
** provide additional information about a preupdate event. These routines |
|
** may only be called from within a preupdate callback. Invoking any of |
|
** these routines from outside of a preupdate callback or with a |
|
** [database connection] pointer that is different from the one supplied |
|
** to the preupdate callback results in undefined and probably undesirable |
|
** behavior. |
|
** |
|
** ^The [sqlite3_preupdate_count(D)] interface returns the number of columns |
|
** in the row that is being inserted, updated, or deleted. |
|
** |
|
** ^The [sqlite3_preupdate_old(D,N,P)] interface writes into P a pointer to |
|
** a [protected sqlite3_value] that contains the value of the Nth column of |
|
** the table row before it is updated. The N parameter must be between 0 |
|
** and one less than the number of columns or the behavior will be |
|
** undefined. This must only be used within SQLITE_UPDATE and SQLITE_DELETE |
|
** preupdate callbacks; if it is used by an SQLITE_INSERT callback then the |
|
** behavior is undefined. The [sqlite3_value] that P points to |
|
** will be destroyed when the preupdate callback returns. |
|
** |
|
** ^The [sqlite3_preupdate_new(D,N,P)] interface writes into P a pointer to |
|
** a [protected sqlite3_value] that contains the value of the Nth column of |
|
** the table row after it is updated. The N parameter must be between 0 |
|
** and one less than the number of columns or the behavior will be |
|
** undefined. This must only be used within SQLITE_INSERT and SQLITE_UPDATE |
|
** preupdate callbacks; if it is used by an SQLITE_DELETE callback then the |
|
** behavior is undefined. The [sqlite3_value] that P points to |
|
** will be destroyed when the preupdate callback returns. |
|
** |
|
** ^The [sqlite3_preupdate_depth(D)] interface returns 0 if the preupdate |
|
** callback was invoked as a result of a direct insert, update, or delete |
|
** operation; or 1 for inserts, updates, or deletes invoked by top-level |
|
** triggers; or 2 for changes resulting from triggers called by top-level |
|
** triggers; and so forth. |
|
** |
|
** See also: [sqlite3_update_hook()] |
|
*/ |
|
SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_preupdate_hook( |
|
sqlite3 *db, |
|
void(*xPreUpdate)( |
|
void *pCtx, /* Copy of third arg to preupdate_hook() */ |
|
sqlite3 *db, /* Database handle */ |
|
int op, /* SQLITE_UPDATE, DELETE or INSERT */ |
|
char const *zDb, /* Database name */ |
|
char const *zName, /* Table name */ |
|
sqlite3_int64 iKey1, /* Rowid of row about to be deleted/updated */ |
|
sqlite3_int64 iKey2 /* New rowid value (for a rowid UPDATE) */ |
|
), |
|
void* |
|
); |
|
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_preupdate_old(sqlite3 *, int, sqlite3_value **); |
|
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_preupdate_count(sqlite3 *); |
|
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_preupdate_depth(sqlite3 *); |
|
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_preupdate_new(sqlite3 *, int, sqlite3_value **); |
|
|
|
/* |
|
** CAPI3REF: Low-level system error code |
|
** |
|
** ^Attempt to return the underlying operating system error code or error |
|
** number that caused the most recent I/O error or failure to open a file. |
|
** The return value is OS-dependent. For example, on unix systems, after |
|
** [sqlite3_open_v2()] returns [SQLITE_CANTOPEN], this interface could be |
|
** called to get back the underlying "errno" that caused the problem, such |
|
** as ENOSPC, EAUTH, EISDIR, and so forth. |
|
*/ |
|
SQLITE_API int sqlite3_system_errno(sqlite3*); |
|
|
|
/* |
|
** CAPI3REF: Database Snapshot |
|
** KEYWORDS: {snapshot} |
|
** EXPERIMENTAL |
|
** |
|
** An instance of the snapshot object records the state of a [WAL mode] |
|
** database for some specific point in history. |
|
** |
|
** In [WAL mode], multiple [database connections] that are open on the |
|
** same database file can each be reading a different historical version |
|
** of the database file. When a [database connection] begins a read |
|
** transaction, that connection sees an unchanging copy of the database |
|
** as it existed for the point in time when the transaction first started. |
|
** Subsequent changes to the database from other connections are not seen |
|
** by the reader until a new read transaction is started. |
|
** |
|
** The sqlite3_snapshot object records state information about an historical |
|
** version of the database file so that it is possible to later open a new read |
|
** transaction that sees that historical version of the database rather than |
|
** the most recent version. |
|
** |
|
** The constructor for this object is [sqlite3_snapshot_get()]. The |
|
** [sqlite3_snapshot_open()] method causes a fresh read transaction to refer |
|
** to an historical snapshot (if possible). The destructor for |
|
** sqlite3_snapshot objects is [sqlite3_snapshot_free()]. |
|
*/ |
|
typedef struct sqlite3_snapshot sqlite3_snapshot; |
|
|
|
/* |
|
** CAPI3REF: Record A Database Snapshot |
|
** EXPERIMENTAL |
|
** |
|
** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a |
|
** new [sqlite3_snapshot] object that records the current state of |
|
** schema S in database connection D. ^On success, the |
|
** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly |
|
** created [sqlite3_snapshot] object into *P and returns SQLITE_OK. |
|
** ^If schema S of [database connection] D is not a [WAL mode] database |
|
** that is in a read transaction, then [sqlite3_snapshot_get(D,S,P)] |
|
** leaves the *P value unchanged and returns an appropriate [error code]. |
|
** |
|
** The [sqlite3_snapshot] object returned from a successful call to |
|
** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()] |
|
** to avoid a memory leak. |
|
** |
|
** The [sqlite3_snapshot_get()] interface is only available when the |
|
** SQLITE_ENABLE_SNAPSHOT compile-time option is used. |
|
*/ |
|
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_get( |
|
sqlite3 *db, |
|
const char *zSchema, |
|
sqlite3_snapshot **ppSnapshot |
|
); |
|
|
|
/* |
|
** CAPI3REF: Start a read transaction on an historical snapshot |
|
** EXPERIMENTAL |
|
** |
|
** ^The [sqlite3_snapshot_open(D,S,P)] interface starts a |
|
** read transaction for schema S of |
|
** [database connection] D such that the read transaction |
|
** refers to historical [snapshot] P, rather than the most |
|
** recent change to the database. |
|
** ^The [sqlite3_snapshot_open()] interface returns SQLITE_OK on success |
|
** or an appropriate [error code] if it fails. |
|
** |
|
** ^In order to succeed, a call to [sqlite3_snapshot_open(D,S,P)] must be |
|
** the first operation following the [BEGIN] that takes the schema S |
|
** out of [autocommit mode]. |
|
** ^In other words, schema S must not currently be in |
|
** a transaction for [sqlite3_snapshot_open(D,S,P)] to work, but the |
|
** database connection D must be out of [autocommit mode]. |
|
** ^A [snapshot] will fail to open if it has been overwritten by a |
|
** [checkpoint]. |
|
** ^(A call to [sqlite3_snapshot_open(D,S,P)] will fail if the |
|
** database connection D does not know that the database file for |
|
** schema S is in [WAL mode]. A database connection might not know |
|
** that the database file is in [WAL mode] if there has been no prior |
|
** I/O on that database connection, or if the database entered [WAL mode] |
|
** after the most recent I/O on the database connection.)^ |
|
** (Hint: Run "[PRAGMA application_id]" against a newly opened |
|
** database connection in order to make it ready to use snapshots.) |
|
** |
|
** The [sqlite3_snapshot_open()] interface is only available when the |
|
** SQLITE_ENABLE_SNAPSHOT compile-time option is used. |
|
*/ |
|
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_open( |
|
sqlite3 *db, |
|
const char *zSchema, |
|
sqlite3_snapshot *pSnapshot |
|
); |
|
|
|
/* |
|
** CAPI3REF: Destroy a snapshot |
|
** EXPERIMENTAL |
|
** |
|
** ^The [sqlite3_snapshot_free(P)] interface destroys [sqlite3_snapshot] P. |
|
** The application must eventually free every [sqlite3_snapshot] object |
|
** using this routine to avoid a memory leak. |
|
** |
|
** The [sqlite3_snapshot_free()] interface is only available when the |
|
** SQLITE_ENABLE_SNAPSHOT compile-time option is used. |
|
*/ |
|
SQLITE_API SQLITE_EXPERIMENTAL void sqlite3_snapshot_free(sqlite3_snapshot*); |
|
|
|
/* |
|
** CAPI3REF: Compare the ages of two snapshot handles. |
|
** EXPERIMENTAL |
|
** |
|
** The sqlite3_snapshot_cmp(P1, P2) interface is used to compare the ages |
|
** of two valid snapshot handles. |
|
** |
|
** If the two snapshot handles are not associated with the same database |
|
** file, the result of the comparison is undefined. |
|
** |
|
** Additionally, the result of the comparison is only valid if both of the |
|
** snapshot handles were obtained by calling sqlite3_snapshot_get() since the |
|
** last time the wal file was deleted. The wal file is deleted when the |
|
** database is changed back to rollback mode or when the number of database |
|
** clients drops to zero. If either snapshot handle was obtained before the |
|
** wal file was last deleted, the value returned by this function |
|
** is undefined. |
|
** |
|
** Otherwise, this API returns a negative value if P1 refers to an older |
|
** snapshot than P2, zero if the two handles refer to the same database |
|
** snapshot, and a positive value if P1 is a newer snapshot than P2. |
|
*/ |
|
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_cmp( |
|
sqlite3_snapshot *p1, |
|
sqlite3_snapshot *p2 |
|
); |
|
|
|
/* |
|
** Undo the hack that converts floating point types to integer for |
|
** builds on processors without floating point support. |
|
*/ |
|
#ifdef SQLITE_OMIT_FLOATING_POINT |
|
# undef double |
|
#endif |
|
|
|
#ifdef __cplusplus |
|
} /* End of the 'extern "C"' block */ |
|
#endif |
|
#endif /* SQLITE3_H */ |
|
|
|
/******** Begin file sqlite3rtree.h *********/ |
|
/* |
|
** 2010 August 30 |
|
** |
|
** The author disclaims copyright to this source code. In place of |
|
** a legal notice, here is a blessing: |
|
** |
|
** May you do good and not evil. |
|
** May you find forgiveness for yourself and forgive others. |
|
** May you share freely, never taking more than you give. |
|
** |
|
************************************************************************* |
|
*/ |
|
|
|
#ifndef _SQLITE3RTREE_H_ |
|
#define _SQLITE3RTREE_H_ |
|
|
|
|
|
#ifdef __cplusplus |
|
extern "C" { |
|
#endif |
|
|
|
typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry; |
|
typedef struct sqlite3_rtree_query_info sqlite3_rtree_query_info; |
|
|
|
/* The double-precision datatype used by RTree depends on the |
|
** SQLITE_RTREE_INT_ONLY compile-time option. |
|
*/ |
|
#ifdef SQLITE_RTREE_INT_ONLY |
|
typedef sqlite3_int64 sqlite3_rtree_dbl; |
|
#else |
|
typedef double sqlite3_rtree_dbl; |
|
#endif |
|
|
|
/* |
|
** Register a geometry callback named zGeom that can be used as part of an |
|
** R-Tree geometry query as follows: |
|
** |
|
** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...) |
|
*/ |
|
SQLITE_API int sqlite3_rtree_geometry_callback( |
|
sqlite3 *db, |
|
const char *zGeom, |
|
int (*xGeom)(sqlite3_rtree_geometry*, int, sqlite3_rtree_dbl*,int*), |
|
void *pContext |
|
); |
|
|
|
|
|
/* |
|
** A pointer to a structure of the following type is passed as the first |
|
** argument to callbacks registered using rtree_geometry_callback(). |
|
*/ |
|
struct sqlite3_rtree_geometry { |
|
void *pContext; /* Copy of pContext passed to s_r_g_c() */ |
|
int nParam; /* Size of array aParam[] */ |
|
sqlite3_rtree_dbl *aParam; /* Parameters passed to SQL geom function */ |
|
void *pUser; /* Callback implementation user data */ |
|
void (*xDelUser)(void *); /* Called by SQLite to clean up pUser */ |
|
}; |
|
|
|
/* |
|
** Register a 2nd-generation geometry callback named zScore that can be |
|
** used as part of an R-Tree geometry query as follows: |
|
** |
|
** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zQueryFunc(... params ...) |
|
*/ |
|
SQLITE_API int sqlite3_rtree_query_callback( |
|
sqlite3 *db, |
|
const char *zQueryFunc, |
|
int (*xQueryFunc)(sqlite3_rtree_query_info*), |
|
void *pContext, |
|
void (*xDestructor)(void*) |
|
); |
|
|
|
|
|
/* |
|
** A pointer to a structure of the following type is passed as the |
|
** argument to scored geometry callback registered using |
|
** sqlite3_rtree_query_callback(). |
|
** |
|
** Note that the first 5 fields of this structure are identical to |
|
** sqlite3_rtree_geometry. This structure is a subclass of |
|
** sqlite3_rtree_geometry. |
|
*/ |
|
struct sqlite3_rtree_query_info { |
|
void *pContext; /* pContext from when function registered */ |
|
int nParam; /* Number of function parameters */ |
|
sqlite3_rtree_dbl *aParam; /* value of function parameters */ |
|
void *pUser; /* callback can use this, if desired */ |
|
void (*xDelUser)(void*); /* function to free pUser */ |
|
sqlite3_rtree_dbl *aCoord; /* Coordinates of node or entry to check */ |
|
unsigned int *anQueue; /* Number of pending entries in the queue */ |
|
int nCoord; /* Number of coordinates */ |
|
int iLevel; /* Level of current node or entry */ |
|
int mxLevel; /* The largest iLevel value in the tree */ |
|
sqlite3_int64 iRowid; /* Rowid for current entry */ |
|
sqlite3_rtree_dbl rParentScore; /* Score of parent node */ |
|
int eParentWithin; /* Visibility of parent node */ |
|
int eWithin; /* OUT: Visiblity */ |
|
sqlite3_rtree_dbl rScore; /* OUT: Write the score here */ |
|
/* The following fields are only available in 3.8.11 and later */ |
|
sqlite3_value **apSqlParam; /* Original SQL values of parameters */ |
|
}; |
|
|
|
/* |
|
** Allowed values for sqlite3_rtree_query.eWithin and .eParentWithin. |
|
*/ |
|
#define NOT_WITHIN 0 /* Object completely outside of query region */ |
|
#define PARTLY_WITHIN 1 /* Object partially overlaps query region */ |
|
#define FULLY_WITHIN 2 /* Object fully contained within query region */ |
|
|
|
|
|
#ifdef __cplusplus |
|
} /* end of the 'extern "C"' block */ |
|
#endif |
|
|
|
#endif /* ifndef _SQLITE3RTREE_H_ */ |
|
|
|
/******** End of sqlite3rtree.h *********/ |
|
/******** Begin file sqlite3session.h *********/ |
|
|
|
#if !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) |
|
#define __SQLITESESSION_H_ 1 |
|
|
|
/* |
|
** Make sure we can call this stuff from C++. |
|
*/ |
|
#ifdef __cplusplus |
|
extern "C" { |
|
#endif |
|
|
|
|
|
/* |
|
** CAPI3REF: Session Object Handle |
|
*/ |
|
typedef struct sqlite3_session sqlite3_session; |
|
|
|
/* |
|
** CAPI3REF: Changeset Iterator Handle |
|
*/ |
|
typedef struct sqlite3_changeset_iter sqlite3_changeset_iter; |
|
|
|
/* |
|
** CAPI3REF: Create A New Session Object |
|
** |
|
** Create a new session object attached to database handle db. If successful, |
|
** a pointer to the new object is written to *ppSession and SQLITE_OK is |
|
** returned. If an error occurs, *ppSession is set to NULL and an SQLite |
|
** error code (e.g. SQLITE_NOMEM) is returned. |
|
** |
|
** It is possible to create multiple session objects attached to a single |
|
** database handle. |
|
** |
|
** Session objects created using this function should be deleted using the |
|
** [sqlite3session_delete()] function before the database handle that they |
|
** are attached to is itself closed. If the database handle is closed before |
|
** the session object is deleted, then the results of calling any session |
|
** module function, including [sqlite3session_delete()] on the session object |
|
** are undefined. |
|
** |
|
** Because the session module uses the [sqlite3_preupdate_hook()] API, it |
|
** is not possible for an application to register a pre-update hook on a |
|
** database handle that has one or more session objects attached. Nor is |
|
** it possible to create a session object attached to a database handle for |
|
** which a pre-update hook is already defined. The results of attempting |
|
** either of these things are undefined. |
|
** |
|
** The session object will be used to create changesets for tables in |
|
** database zDb, where zDb is either "main", or "temp", or the name of an |
|
** attached database. It is not an error if database zDb is not attached |
|
** to the database when the session object is created. |
|
*/ |
|
int sqlite3session_create( |
|
sqlite3 *db, /* Database handle */ |
|
const char *zDb, /* Name of db (e.g. "main") */ |
|
sqlite3_session **ppSession /* OUT: New session object */ |
|
); |
|
|
|
/* |
|
** CAPI3REF: Delete A Session Object |
|
** |
|
** Delete a session object previously allocated using |
|
** [sqlite3session_create()]. Once a session object has been deleted, the |
|
** results of attempting to use pSession with any other session module |
|
** function are undefined. |
|
** |
|
** Session objects must be deleted before the database handle to which they |
|
** are attached is closed. Refer to the documentation for |
|
** [sqlite3session_create()] for details. |
|
*/ |
|
void sqlite3session_delete(sqlite3_session *pSession); |
|
|
|
|
|
/* |
|
** CAPI3REF: Enable Or Disable A Session Object |
|
** |
|
** Enable or disable the recording of changes by a session object. When |
|
** enabled, a session object records changes made to the database. When |
|
** disabled - it does not. A newly created session object is enabled. |
|
** Refer to the documentation for [sqlite3session_changeset()] for further |
|
** details regarding how enabling and disabling a session object affects |
|
** the eventual changesets. |
|
** |
|
** Passing zero to this function disables the session. Passing a value |
|
** greater than zero enables it. Passing a value less than zero is a |
|
** no-op, and may be used to query the current state of the session. |
|
** |
|
** The return value indicates the final state of the session object: 0 if |
|
** the session is disabled, or 1 if it is enabled. |
|
*/ |
|
int sqlite3session_enable(sqlite3_session *pSession, int bEnable); |
|
|
|
/* |
|
** CAPI3REF: Set Or Clear the Indirect Change Flag |
|
** |
|
** Each change recorded by a session object is marked as either direct or |
|
** indirect. A change is marked as indirect if either: |
|
** |
|
** <ul> |
|
** <li> The session object "indirect" flag is set when the change is |
|
** made, or |
|
** <li> The change is made by an SQL trigger or foreign key action |
|
** instead of directly as a result of a users SQL statement. |
|
** </ul> |
|
** |
|
** If a single row is affected by more than one operation within a session, |
|
** then the change is considered indirect if all operations meet the criteria |
|
** for an indirect change above, or direct otherwise. |
|
** |
|
** This function is used to set, clear or query the session object indirect |
|
** flag. If the second argument passed to this function is zero, then the |
|
** indirect flag is cleared. If it is greater than zero, the indirect flag |
|
** is set. Passing a value less than zero does not modify the current value |
|
** of the indirect flag, and may be used to query the current state of the |
|
** indirect flag for the specified session object. |
|
** |
|
** The return value indicates the final state of the indirect flag: 0 if |
|
** it is clear, or 1 if it is set. |
|
*/ |
|
int sqlite3session_indirect(sqlite3_session *pSession, int bIndirect); |
|
|
|
/* |
|
** CAPI3REF: Attach A Table To A Session Object |
|
** |
|
** If argument zTab is not NULL, then it is the name of a table to attach |
|
** to the session object passed as the first argument. All subsequent changes |
|
** made to the table while the session object is enabled will be recorded. See |
|
** documentation for [sqlite3session_changeset()] for further details. |
|
** |
|
** Or, if argument zTab is NULL, then changes are recorded for all tables |
|
** in the database. If additional tables are added to the database (by |
|
** executing "CREATE TABLE" statements) after this call is made, changes for |
|
** the new tables are also recorded. |
|
** |
|
** Changes can only be recorded for tables that have a PRIMARY KEY explicitly |
|
** defined as part of their CREATE TABLE statement. It does not matter if the |
|
** PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias) or not. The PRIMARY |
|
** KEY may consist of a single column, or may be a composite key. |
|
** |
|
** It is not an error if the named table does not exist in the database. Nor |
|
** is it an error if the named table does not have a PRIMARY KEY. However, |
|
** no changes will be recorded in either of these scenarios. |
|
** |
|
** Changes are not recorded for individual rows that have NULL values stored |
|
** in one or more of their PRIMARY KEY columns. |
|
** |
|
** SQLITE_OK is returned if the call completes without error. Or, if an error |
|
** occurs, an SQLite error code (e.g. SQLITE_NOMEM) is returned. |
|
*/ |
|
int sqlite3session_attach( |
|
sqlite3_session *pSession, /* Session object */ |
|
const char *zTab /* Table name */ |
|
); |
|
|
|
/* |
|
** CAPI3REF: Set a table filter on a Session Object. |
|
** |
|
** The second argument (xFilter) is the "filter callback". For changes to rows |
|
** in tables that are not attached to the Session object, the filter is called |
|
** to determine whether changes to the table's rows should be tracked or not. |
|
** If xFilter returns 0, changes is not tracked. Note that once a table is |
|
** attached, xFilter will not be called again. |
|
*/ |
|
void sqlite3session_table_filter( |
|
sqlite3_session *pSession, /* Session object */ |
|
int(*xFilter)( |
|
void *pCtx, /* Copy of third arg to _filter_table() */ |
|
const char *zTab /* Table name */ |
|
), |
|
void *pCtx /* First argument passed to xFilter */ |
|
); |
|
|
|
/* |
|
** CAPI3REF: Generate A Changeset From A Session Object |
|
** |
|
** Obtain a changeset containing changes to the tables attached to the |
|
** session object passed as the first argument. If successful, |
|
** set *ppChangeset to point to a buffer containing the changeset |
|
** and *pnChangeset to the size of the changeset in bytes before returning |
|
** SQLITE_OK. If an error occurs, set both *ppChangeset and *pnChangeset to |
|
** zero and return an SQLite error code. |
|
** |
|
** A changeset consists of zero or more INSERT, UPDATE and/or DELETE changes, |
|
** each representing a change to a single row of an attached table. An INSERT |
|
** change contains the values of each field of a new database row. A DELETE |
|
** contains the original values of each field of a deleted database row. An |
|
** UPDATE change contains the original values of each field of an updated |
|
** database row along with the updated values for each updated non-primary-key |
|
** column. It is not possible for an UPDATE change to represent a change that |
|
** modifies the values of primary key columns. If such a change is made, it |
|
** is represented in a changeset as a DELETE followed by an INSERT. |
|
** |
|
** Changes are not recorded for rows that have NULL values stored in one or |
|
** more of their PRIMARY KEY columns. If such a row is inserted or deleted, |
|
** no corresponding change is present in the changesets returned by this |
|
** function. If an existing row with one or more NULL values stored in |
|
** PRIMARY KEY columns is updated so that all PRIMARY KEY columns are non-NULL, |
|
** only an INSERT is appears in the changeset. Similarly, if an existing row |
|
** with non-NULL PRIMARY KEY values is updated so that one or more of its |
|
** PRIMARY KEY columns are set to NULL, the resulting changeset contains a |
|
** DELETE change only. |
|
** |
|
** The contents of a changeset may be traversed using an iterator created |
|
** using the [sqlite3changeset_start()] API. A changeset may be applied to |
|
** a database with a compatible schema using the [sqlite3changeset_apply()] |
|
** API. |
|
** |
|
** Within a changeset generated by this function, all changes related to a |
|
** single table are grouped together. In other words, when iterating through |
|
** a changeset or when applying a changeset to a database, all changes related |
|
** to a single table are processed before moving on to the next table. Tables |
|
** are sorted in the same order in which they were attached (or auto-attached) |
|
** to the sqlite3_session object. The order in which the changes related to |
|
** a single table are stored is undefined. |
|
** |
|
** Following a successful call to this function, it is the responsibility of |
|
** the caller to eventually free the buffer that *ppChangeset points to using |
|
** [sqlite3_free()]. |
|
** |
|
** <h3>Changeset Generation</h3> |
|
** |
|
** Once a table has been attached to a session object, the session object |
|
** records the primary key values of all new rows inserted into the table. |
|
** It also records the original primary key and other column values of any |
|
** deleted or updated rows. For each unique primary key value, data is only |
|
** recorded once - the first time a row with said primary key is inserted, |
|
** updated or deleted in the lifetime of the session. |
|
** |
|
** There is one exception to the previous paragraph: when a row is inserted, |
|
** updated or deleted, if one or more of its primary key columns contain a |
|
** NULL value, no record of the change is made. |
|
** |
|
** The session object therefore accumulates two types of records - those |
|
** that consist of primary key values only (created when the user inserts |
|
** a new record) and those that consist of the primary key values and the |
|
** original values of other table columns (created when the users deletes |
|
** or updates a record). |
|
** |
|
** When this function is called, the requested changeset is created using |
|
** both the accumulated records and the current contents of the database |
|
** file. Specifically: |
|
** |
|
** <ul> |
|
** <li> For each record generated by an insert, the database is queried |
|
** for a row with a matching primary key. If one is found, an INSERT |
|
** change is added to the changeset. If no such row is found, no change |
|
** is added to the changeset. |
|
** |
|
** <li> For each record generated by an update or delete, the database is |
|
** queried for a row with a matching primary key. If such a row is |
|
** found and one or more of the non-primary key fields have been |
|
** modified from their original values, an UPDATE change is added to |
|
** the changeset. Or, if no such row is found in the table, a DELETE |
|
** change is added to the changeset. If there is a row with a matching |
|
** primary key in the database, but all fields contain their original |
|
** values, no change is added to the changeset. |
|
** </ul> |
|
** |
|
** This means, amongst other things, that if a row is inserted and then later |
|
** deleted while a session object is active, neither the insert nor the delete |
|
** will be present in the changeset. Or if a row is deleted and then later a |
|
** row with the same primary key values inserted while a session object is |
|
** active, the resulting changeset will contain an UPDATE change instead of |
|
** a DELETE and an INSERT. |
|
** |
|
** When a session object is disabled (see the [sqlite3session_enable()] API), |
|
** it does not accumulate records when rows are inserted, updated or deleted. |
|
** This may appear to have some counter-intuitive effects if a single row |
|
** is written to more than once during a session. For example, if a row |
|
** is inserted while a session object is enabled, then later deleted while |
|
** the same session object is disabled, no INSERT record will appear in the |
|
** changeset, even though the delete took place while the session was disabled. |
|
** Or, if one field of a row is updated while a session is disabled, and |
|
** another field of the same row is updated while the session is enabled, the |
|
** resulting changeset will contain an UPDATE change that updates both fields. |
|
*/ |
|
int sqlite3session_changeset( |
|
sqlite3_session *pSession, /* Session object */ |
|
int *pnChangeset, /* OUT: Size of buffer at *ppChangeset */ |
|
void **ppChangeset /* OUT: Buffer containing changeset */ |
|
); |
|
|
|
/* |
|
** CAPI3REF: Load The Difference Between Tables Into A Session |
|
** |
|
** If it is not already attached to the session object passed as the first |
|
** argument, this function attaches table zTbl in the same manner as the |
|
** [sqlite3session_attach()] function. If zTbl does not exist, or if it |
|
** does not have a primary key, this function is a no-op (but does not return |
|
** an error). |
|
** |
|
** Argument zFromDb must be the name of a database ("main", "temp" etc.) |
|
** attached to the same database handle as the session object that contains |
|
** a table compatible with the table attached to the session by this function. |
|
** A table is considered compatible if it: |
|
** |
|
** <ul> |
|
** <li> Has the same name, |
|
** <li> Has the same set of columns declared in the same order, and |
|
** <li> Has the same PRIMARY KEY definition. |
|
** </ul> |
|
** |
|
** If the tables are not compatible, SQLITE_SCHEMA is returned. If the tables |
|
** are compatible but do not have any PRIMARY KEY columns, it is not an error |
|
** but no changes are added to the session object. As with other session |
|
** APIs, tables without PRIMARY KEYs are simply ignored. |
|
** |
|
** This function adds a set of changes to the session object that could be |
|
** used to update the table in database zFrom (call this the "from-table") |
|
** so that its content is the same as the table attached to the session |
|
** object (call this the "to-table"). Specifically: |
|
** |
|
** <ul> |
|
** <li> For each row (primary key) that exists in the to-table but not in |
|
** the from-table, an INSERT record is added to the session object. |
|
** |
|
** <li> For each row (primary key) that exists in the to-table but not in |
|
** the from-table, a DELETE record is added to the session object. |
|
** |
|
** <li> For each row (primary key) that exists in both tables, but features |
|
** different in each, an UPDATE record is added to the session. |
|
** </ul> |
|
** |
|
** To clarify, if this function is called and then a changeset constructed |
|
** using [sqlite3session_changeset()], then after applying that changeset to |
|
** database zFrom the contents of the two compatible tables would be |
|
** identical. |
|
** |
|
** It an error if database zFrom does not exist or does not contain the |
|
** required compatible table. |
|
** |
|
** If the operation successful, SQLITE_OK is returned. Otherwise, an SQLite |
|
** error code. In this case, if argument pzErrMsg is not NULL, *pzErrMsg |
|
** may be set to point to a buffer containing an English language error |
|
** message. It is the responsibility of the caller to free this buffer using |
|
** sqlite3_free(). |
|
*/ |
|
int sqlite3session_diff( |
|
sqlite3_session *pSession, |
|
const char *zFromDb, |
|
const char *zTbl, |
|
char **pzErrMsg |
|
); |
|
|
|
|
|
/* |
|
** CAPI3REF: Generate A Patchset From A Session Object |
|
** |
|
** The differences between a patchset and a changeset are that: |
|
** |
|
** <ul> |
|
** <li> DELETE records consist of the primary key fields only. The |
|
** original values of other fields are omitted. |
|
** <li> The original values of any modified fields are omitted from |
|
** UPDATE records. |
|
** </ul> |
|
** |
|
** A patchset blob may be used with up to date versions of all |
|
** sqlite3changeset_xxx API functions except for sqlite3changeset_invert(), |
|
** which returns SQLITE_CORRUPT if it is passed a patchset. Similarly, |
|
** attempting to use a patchset blob with old versions of the |
|
** sqlite3changeset_xxx APIs also provokes an SQLITE_CORRUPT error. |
|
** |
|
** Because the non-primary key "old.*" fields are omitted, no |
|
** SQLITE_CHANGESET_DATA conflicts can be detected or reported if a patchset |
|
** is passed to the sqlite3changeset_apply() API. Other conflict types work |
|
** in the same way as for changesets. |
|
** |
|
** Changes within a patchset are ordered in the same way as for changesets |
|
** generated by the sqlite3session_changeset() function (i.e. all changes for |
|
** a single table are grouped together, tables appear in the order in which |
|
** they were attached to the session object). |
|
*/ |
|
int sqlite3session_patchset( |
|
sqlite3_session *pSession, /* Session object */ |
|
int *pnPatchset, /* OUT: Size of buffer at *ppChangeset */ |
|
void **ppPatchset /* OUT: Buffer containing changeset */ |
|
); |
|
|
|
/* |
|
** CAPI3REF: Test if a changeset has recorded any changes. |
|
** |
|
** Return non-zero if no changes to attached tables have been recorded by |
|
** the session object passed as the first argument. Otherwise, if one or |
|
** more changes have been recorded, return zero. |
|
** |
|
** Even if this function returns zero, it is possible that calling |
|
** [sqlite3session_changeset()] on the session handle may still return a |
|
** changeset that contains no changes. This can happen when a row in |
|
** an attached table is modified and then later on the original values |
|
** are restored. However, if this function returns non-zero, then it is |
|
** guaranteed that a call to sqlite3session_changeset() will return a |
|
** changeset containing zero changes. |
|
*/ |
|
int sqlite3session_isempty(sqlite3_session *pSession); |
|
|
|
/* |
|
** CAPI3REF: Create An Iterator To Traverse A Changeset |
|
** |
|
** Create an iterator used to iterate through the contents of a changeset. |
|
** If successful, *pp is set to point to the iterator handle and SQLITE_OK |
|
** is returned. Otherwise, if an error occurs, *pp is set to zero and an |
|
** SQLite error code is returned. |
|
** |
|
** The following functions can be used to advance and query a changeset |
|
** iterator created by this function: |
|
** |
|
** <ul> |
|
** <li> [sqlite3changeset_next()] |
|
** <li> [sqlite3changeset_op()] |
|
** <li> [sqlite3changeset_new()] |
|
** <li> [sqlite3changeset_old()] |
|
** </ul> |
|
** |
|
** It is the responsibility of the caller to eventually destroy the iterator |
|
** by passing it to [sqlite3changeset_finalize()]. The buffer containing the |
|
** changeset (pChangeset) must remain valid until after the iterator is |
|
** destroyed. |
|
** |
|
** Assuming the changeset blob was created by one of the |
|
** [sqlite3session_changeset()], [sqlite3changeset_concat()] or |
|
** [sqlite3changeset_invert()] functions, all changes within the changeset |
|
** that apply to a single table are grouped together. This means that when |
|
** an application iterates through a changeset using an iterator created by |
|
** this function, all changes that relate to a single table are visited |
|
** consecutively. There is no chance that the iterator will visit a change |
|
** the applies to table X, then one for table Y, and then later on visit |
|
** another change for table X. |
|
*/ |
|
int sqlite3changeset_start( |
|
sqlite3_changeset_iter **pp, /* OUT: New changeset iterator handle */ |
|
int nChangeset, /* Size of changeset blob in bytes */ |
|
void *pChangeset /* Pointer to blob containing changeset */ |
|
); |
|
|
|
|
|
/* |
|
** CAPI3REF: Advance A Changeset Iterator |
|
** |
|
** This function may only be used with iterators created by function |
|
** [sqlite3changeset_start()]. If it is called on an iterator passed to |
|
** a conflict-handler callback by [sqlite3changeset_apply()], SQLITE_MISUSE |
|
** is returned and the call has no effect. |
|
** |
|
** Immediately after an iterator is created by sqlite3changeset_start(), it |
|
** does not point to any change in the changeset. Assuming the changeset |
|
** is not empty, the first call to this function advances the iterator to |
|
** point to the first change in the changeset. Each subsequent call advances |
|
** the iterator to point to the next change in the changeset (if any). If |
|
** no error occurs and the iterator points to a valid change after a call |
|
** to sqlite3changeset_next() has advanced it, SQLITE_ROW is returned. |
|
** Otherwise, if all changes in the changeset have already been visited, |
|
** SQLITE_DONE is returned. |
|
** |
|
** If an error occurs, an SQLite error code is returned. Possible error |
|
** codes include SQLITE_CORRUPT (if the changeset buffer is corrupt) or |
|
** SQLITE_NOMEM. |
|
*/ |
|
int sqlite3changeset_next(sqlite3_changeset_iter *pIter); |
|
|
|
/* |
|
** CAPI3REF: Obtain The Current Operation From A Changeset Iterator |
|
** |
|
** The pIter argument passed to this function may either be an iterator |
|
** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator |
|
** created by [sqlite3changeset_start()]. In the latter case, the most recent |
|
** call to [sqlite3changeset_next()] must have returned [SQLITE_ROW]. If this |
|
** is not the case, this function returns [SQLITE_MISUSE]. |
|
** |
|
** If argument pzTab is not NULL, then *pzTab is set to point to a |
|
** nul-terminated utf-8 encoded string containing the name of the table |
|
** affected by the current change. The buffer remains valid until either |
|
** sqlite3changeset_next() is called on the iterator or until the |
|
** conflict-handler function returns. If pnCol is not NULL, then *pnCol is |
|
** set to the number of columns in the table affected by the change. If |
|
** pbIncorrect is not NULL, then *pbIndirect is set to true (1) if the change |
|
** is an indirect change, or false (0) otherwise. See the documentation for |
|
** [sqlite3session_indirect()] for a description of direct and indirect |
|
** changes. Finally, if pOp is not NULL, then *pOp is set to one of |
|
** [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE], depending on the |
|
** type of change that the iterator currently points to. |
|
** |
|
** If no error occurs, SQLITE_OK is returned. If an error does occur, an |
|
** SQLite error code is returned. The values of the output variables may not |
|
** be trusted in this case. |
|
*/ |
|
int sqlite3changeset_op( |
|
sqlite3_changeset_iter *pIter, /* Iterator object */ |
|
const char **pzTab, /* OUT: Pointer to table name */ |
|
int *pnCol, /* OUT: Number of columns in table */ |
|
int *pOp, /* OUT: SQLITE_INSERT, DELETE or UPDATE */ |
|
int *pbIndirect /* OUT: True for an 'indirect' change */ |
|
); |
|
|
|
/* |
|
** CAPI3REF: Obtain The Primary Key Definition Of A Table |
|
** |
|
** For each modified table, a changeset includes the following: |
|
** |
|
** <ul> |
|
** <li> The number of columns in the table, and |
|
** <li> Which of those columns make up the tables PRIMARY KEY. |
|
** </ul> |
|
** |
|
** This function is used to find which columns comprise the PRIMARY KEY of |
|
** the table modified by the change that iterator pIter currently points to. |
|
** If successful, *pabPK is set to point to an array of nCol entries, where |
|
** nCol is the number of columns in the table. Elements of *pabPK are set to |
|
** 0x01 if the corresponding column is part of the tables primary key, or |
|
** 0x00 if it is not. |
|
** |
|
** If argument pnCol is not NULL, then *pnCol is set to the number of columns |
|
** in the table. |
|
** |
|
** If this function is called when the iterator does not point to a valid |
|
** entry, SQLITE_MISUSE is returned and the output variables zeroed. Otherwise, |
|
** SQLITE_OK is returned and the output variables populated as described |
|
** above. |
|
*/ |
|
int sqlite3changeset_pk( |
|
sqlite3_changeset_iter *pIter, /* Iterator object */ |
|
unsigned char **pabPK, /* OUT: Array of boolean - true for PK cols */ |
|
int *pnCol /* OUT: Number of entries in output array */ |
|
); |
|
|
|
/* |
|
** CAPI3REF: Obtain old.* Values From A Changeset Iterator |
|
** |
|
** The pIter argument passed to this function may either be an iterator |
|
** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator |
|
** created by [sqlite3changeset_start()]. In the latter case, the most recent |
|
** call to [sqlite3changeset_next()] must have returned SQLITE_ROW. |
|
** Furthermore, it may only be called if the type of change that the iterator |
|
** currently points to is either [SQLITE_DELETE] or [SQLITE_UPDATE]. Otherwise, |
|
** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL. |
|
** |
|
** Argument iVal must be greater than or equal to 0, and less than the number |
|
** of columns in the table affected by the current change. Otherwise, |
|
** [SQLITE_RANGE] is returned and *ppValue is set to NULL. |
|
** |
|
** If successful, this function sets *ppValue to point to a protected |
|
** sqlite3_value object containing the iVal'th value from the vector of |
|
** original row values stored as part of the UPDATE or DELETE change and |
|
** returns SQLITE_OK. The name of the function comes from the fact that this |
|
** is similar to the "old.*" columns available to update or delete triggers. |
|
** |
|
** If some other error occurs (e.g. an OOM condition), an SQLite error code |
|
** is returned and *ppValue is set to NULL. |
|
*/ |
|
int sqlite3changeset_old( |
|
sqlite3_changeset_iter *pIter, /* Changeset iterator */ |
|
int iVal, /* Column number */ |
|
sqlite3_value **ppValue /* OUT: Old value (or NULL pointer) */ |
|
); |
|
|
|
/* |
|
** CAPI3REF: Obtain new.* Values From A Changeset Iterator |
|
** |
|
** The pIter argument passed to this function may either be an iterator |
|
** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator |
|
** created by [sqlite3changeset_start()]. In the latter case, the most recent |
|
** call to [sqlite3changeset_next()] must have returned SQLITE_ROW. |
|
** Furthermore, it may only be called if the type of change that the iterator |
|
** currently points to is either [SQLITE_UPDATE] or [SQLITE_INSERT]. Otherwise, |
|
** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL. |
|
** |
|
** Argument iVal must be greater than or equal to 0, and less than the number |
|
** of columns in the table affected by the current change. Otherwise, |
|
** [SQLITE_RANGE] is returned and *ppValue is set to NULL. |
|
** |
|
** If successful, this function sets *ppValue to point to a protected |
|
** sqlite3_value object containing the iVal'th value from the vector of |
|
** new row values stored as part of the UPDATE or INSERT change and |
|
** returns SQLITE_OK. If the change is an UPDATE and does not include |
|
** a new value for the requested column, *ppValue is set to NULL and |
|
** SQLITE_OK returned. The name of the function comes from the fact that |
|
** this is similar to the "new.*" columns available to update or delete |
|
** triggers. |
|
** |
|
** If some other error occurs (e.g. an OOM condition), an SQLite error code |
|
** is returned and *ppValue is set to NULL. |
|
*/ |
|
int sqlite3changeset_new( |
|
sqlite3_changeset_iter *pIter, /* Changeset iterator */ |
|
int iVal, /* Column number */ |
|
sqlite3_value **ppValue /* OUT: New value (or NULL pointer) */ |
|
); |
|
|
|
/* |
|
** CAPI3REF: Obtain Conflicting Row Values From A Changeset Iterator |
|
** |
|
** This function should only be used with iterator objects passed to a |
|
** conflict-handler callback by [sqlite3changeset_apply()] with either |
|
** [SQLITE_CHANGESET_DATA] or [SQLITE_CHANGESET_CONFLICT]. If this function |
|
** is called on any other iterator, [SQLITE_MISUSE] is returned and *ppValue |
|
** is set to NULL. |
|
** |
|
** Argument iVal must be greater than or equal to 0, and less than the number |
|
** of columns in the table affected by the current change. Otherwise, |
|
** [SQLITE_RANGE] is returned and *ppValue is set to NULL. |
|
** |
|
** If successful, this function sets *ppValue to point to a protected |
|
** sqlite3_value object containing the iVal'th value from the |
|
** "conflicting row" associated with the current conflict-handler callback |
|
** and returns SQLITE_OK. |
|
** |
|
** If some other error occurs (e.g. an OOM condition), an SQLite error code |
|
** is returned and *ppValue is set to NULL. |
|
*/ |
|
int sqlite3changeset_conflict( |
|
sqlite3_changeset_iter *pIter, /* Changeset iterator */ |
|
int iVal, /* Column number */ |
|
sqlite3_value **ppValue /* OUT: Value from conflicting row */ |
|
); |
|
|
|
/* |
|
** CAPI3REF: Determine The Number Of Foreign Key Constraint Violations |
|
** |
|
** This function may only be called with an iterator passed to an |
|
** SQLITE_CHANGESET_FOREIGN_KEY conflict handler callback. In this case |
|
** it sets the output variable to the total number of known foreign key |
|
** violations in the destination database and returns SQLITE_OK. |
|
** |
|
** In all other cases this function returns SQLITE_MISUSE. |
|
*/ |
|
int sqlite3changeset_fk_conflicts( |
|
sqlite3_changeset_iter *pIter, /* Changeset iterator */ |
|
int *pnOut /* OUT: Number of FK violations */ |
|
); |
|
|
|
|
|
/* |
|
** CAPI3REF: Finalize A Changeset Iterator |
|
** |
|
** This function is used to finalize an iterator allocated with |
|
** [sqlite3changeset_start()]. |
|
** |
|
** This function should only be called on iterators created using the |
|
** [sqlite3changeset_start()] function. If an application calls this |
|
** function with an iterator passed to a conflict-handler by |
|
** [sqlite3changeset_apply()], [SQLITE_MISUSE] is immediately returned and the |
|
** call has no effect. |
|
** |
|
** If an error was encountered within a call to an sqlite3changeset_xxx() |
|
** function (for example an [SQLITE_CORRUPT] in [sqlite3changeset_next()] or an |
|
** [SQLITE_NOMEM] in [sqlite3changeset_new()]) then an error code corresponding |
|
** to that error is returned by this function. Otherwise, SQLITE_OK is |
|
** returned. This is to allow the following pattern (pseudo-code): |
|
** |
|
** sqlite3changeset_start(); |
|
** while( SQLITE_ROW==sqlite3changeset_next() ){ |
|
** // Do something with change. |
|
** } |
|
** rc = sqlite3changeset_finalize(); |
|
** if( rc!=SQLITE_OK ){ |
|
** // An error has occurred |
|
** } |
|
*/ |
|
int sqlite3changeset_finalize(sqlite3_changeset_iter *pIter); |
|
|
|
/* |
|
** CAPI3REF: Invert A Changeset |
|
** |
|
** This function is used to "invert" a changeset object. Applying an inverted |
|
** changeset to a database reverses the effects of applying the uninverted |
|
** changeset. Specifically: |
|
** |
|
** <ul> |
|
** <li> Each DELETE change is changed to an INSERT, and |
|
** <li> Each INSERT change is changed to a DELETE, and |
|
** <li> For each UPDATE change, the old.* and new.* values are exchanged. |
|
** </ul> |
|
** |
|
** This function does not change the order in which changes appear within |
|
** the changeset. It merely reverses the sense of each individual change. |
|
** |
|
** If successful, a pointer to a buffer containing the inverted changeset |
|
** is stored in *ppOut, the size of the same buffer is stored in *pnOut, and |
|
** SQLITE_OK is returned. If an error occurs, both *pnOut and *ppOut are |
|
** zeroed and an SQLite error code returned. |
|
** |
|
** It is the responsibility of the caller to eventually call sqlite3_free() |
|
** on the *ppOut pointer to free the buffer allocation following a successful |
|
** call to this function. |
|
** |
|
** WARNING/TODO: This function currently assumes that the input is a valid |
|
** changeset. If it is not, the results are undefined. |
|
*/ |
|
int sqlite3changeset_invert( |
|
int nIn, const void *pIn, /* Input changeset */ |
|
int *pnOut, void **ppOut /* OUT: Inverse of input */ |
|
); |
|
|
|
/* |
|
** CAPI3REF: Concatenate Two Changeset Objects |
|
** |
|
** This function is used to concatenate two changesets, A and B, into a |
|
** single changeset. The result is a changeset equivalent to applying |
|
** changeset A followed by changeset B. |
|
** |
|
** This function combines the two input changesets using an |
|
** sqlite3_changegroup object. Calling it produces similar results as the |
|
** following code fragment: |
|
** |
|
** sqlite3_changegroup *pGrp; |
|
** rc = sqlite3_changegroup_new(&pGrp); |
|
** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nA, pA); |
|
** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nB, pB); |
|
** if( rc==SQLITE_OK ){ |
|
** rc = sqlite3changegroup_output(pGrp, pnOut, ppOut); |
|
** }else{ |
|
** *ppOut = 0; |
|
** *pnOut = 0; |
|
** } |
|
** |
|
** Refer to the sqlite3_changegroup documentation below for details. |
|
*/ |
|
int sqlite3changeset_concat( |
|
int nA, /* Number of bytes in buffer pA */ |
|
void *pA, /* Pointer to buffer containing changeset A */ |
|
int nB, /* Number of bytes in buffer pB */ |
|
void *pB, /* Pointer to buffer containing changeset B */ |
|
int *pnOut, /* OUT: Number of bytes in output changeset */ |
|
void **ppOut /* OUT: Buffer containing output changeset */ |
|
); |
|
|
|
|
|
/* |
|
** CAPI3REF: Changegroup Handle |
|
*/ |
|
typedef struct sqlite3_changegroup sqlite3_changegroup; |
|
|
|
/* |
|
** CAPI3REF: Create A New Changegroup Object |
|
** |
|
** An sqlite3_changegroup object is used to combine two or more changesets |
|
** (or patchsets) into a single changeset (or patchset). A single changegroup |
|
** object may combine changesets or patchsets, but not both. The output is |
|
** always in the same format as the input. |
|
** |
|
** If successful, this function returns SQLITE_OK and populates (*pp) with |
|
** a pointer to a new sqlite3_changegroup object before returning. The caller |
|
** should eventually free the returned object using a call to |
|
** sqlite3changegroup_delete(). If an error occurs, an SQLite error code |
|
** (i.e. SQLITE_NOMEM) is returned and *pp is set to NULL. |
|
** |
|
** The usual usage pattern for an sqlite3_changegroup object is as follows: |
|
** |
|
** <ul> |
|
** <li> It is created using a call to sqlite3changegroup_new(). |
|
** |
|
** <li> Zero or more changesets (or patchsets) are added to the object |
|
** by calling sqlite3changegroup_add(). |
|
** |
|
** <li> The result of combining all input changesets together is obtained |
|
** by the application via a call to sqlite3changegroup_output(). |
|
** |
|
** <li> The object is deleted using a call to sqlite3changegroup_delete(). |
|
** </ul> |
|
** |
|
** Any number of calls to add() and output() may be made between the calls to |
|
** new() and delete(), and in any order. |
|
** |
|
** As well as the regular sqlite3changegroup_add() and |
|
** sqlite3changegroup_output() functions, also available are the streaming |
|
** versions sqlite3changegroup_add_strm() and sqlite3changegroup_output_strm(). |
|
*/ |
|
int sqlite3changegroup_new(sqlite3_changegroup **pp); |
|
|
|
/* |
|
** CAPI3REF: Add A Changeset To A Changegroup |
|
** |
|
** Add all changes within the changeset (or patchset) in buffer pData (size |
|
** nData bytes) to the changegroup. |
|
** |
|
** If the buffer contains a patchset, then all prior calls to this function |
|
** on the same changegroup object must also have specified patchsets. Or, if |
|
** the buffer contains a changeset, so must have the earlier calls to this |
|
** function. Otherwise, SQLITE_ERROR is returned and no changes are added |
|
** to the changegroup. |
|
** |
|
** Rows within the changeset and changegroup are identified by the values in |
|
** their PRIMARY KEY columns. A change in the changeset is considered to |
|
** apply to the same row as a change already present in the changegroup if |
|
** the two rows have the same primary key. |
|
** |
|
** Changes to rows that do not already appear in the changegroup are |
|
** simply copied into it. Or, if both the new changeset and the changegroup |
|
** contain changes that apply to a single row, the final contents of the |
|
** changegroup depends on the type of each change, as follows: |
|
** |
|
** <table border=1 style="margin-left:8ex;margin-right:8ex"> |
|
** <tr><th style="white-space:pre">Existing Change </th> |
|
** <th style="white-space:pre">New Change </th> |
|
** <th>Output Change |
|
** <tr><td>INSERT <td>INSERT <td> |
|
** The new change is ignored. This case does not occur if the new |
|
** changeset was recorded immediately after the changesets already |
|
** added to the changegroup. |
|
** <tr><td>INSERT <td>UPDATE <td> |
|
** The INSERT change remains in the changegroup. The values in the |
|
** INSERT change are modified as if the row was inserted by the |
|
** existing change and then updated according to the new change. |
|
** <tr><td>INSERT <td>DELETE <td> |
|
** The existing INSERT is removed from the changegroup. The DELETE is |
|
** not added. |
|
** <tr><td>UPDATE <td>INSERT <td> |
|
** The new change is ignored. This case does not occur if the new |
|
** changeset was recorded immediately after the changesets already |
|
** added to the changegroup. |
|
** <tr><td>UPDATE <td>UPDATE <td> |
|
** The existing UPDATE remains within the changegroup. It is amended |
|
** so that the accompanying values are as if the row was updated once |
|
** by the existing change and then again by the new change. |
|
** <tr><td>UPDATE <td>DELETE <td> |
|
** The existing UPDATE is replaced by the new DELETE within the |
|
** changegroup. |
|
** <tr><td>DELETE <td>INSERT <td> |
|
** If one or more of the column values in the row inserted by the |
|
** new change differ from those in the row deleted by the existing |
|
** change, the existing DELETE is replaced by an UPDATE within the |
|
** changegroup. Otherwise, if the inserted row is exactly the same |
|
** as the deleted row, the existing DELETE is simply discarded. |
|
** <tr><td>DELETE <td>UPDATE <td> |
|
** The new change is ignored. This case does not occur if the new |
|
** changeset was recorded immediately after the changesets already |
|
** added to the changegroup. |
|
** <tr><td>DELETE <td>DELETE <td> |
|
** The new change is ignored. This case does not occur if the new |
|
** changeset was recorded immediately after the changesets already |
|
** added to the changegroup. |
|
** </table> |
|
** |
|
** If the new changeset contains changes to a table that is already present |
|
** in the changegroup, then the number of columns and the position of the |
|
** primary key columns for the table must be consistent. If this is not the |
|
** case, this function fails with SQLITE_SCHEMA. If the input changeset |
|
** appears to be corrupt and the corruption is detected, SQLITE_CORRUPT is |
|
** returned. Or, if an out-of-memory condition occurs during processing, this |
|
** function returns SQLITE_NOMEM. In all cases, if an error occurs the |
|
** final contents of the changegroup is undefined. |
|
** |
|
** If no error occurs, SQLITE_OK is returned. |
|
*/ |
|
int sqlite3changegroup_add(sqlite3_changegroup*, int nData, void *pData); |
|
|
|
/* |
|
** CAPI3REF: Obtain A Composite Changeset From A Changegroup |
|
** |
|
** Obtain a buffer containing a changeset (or patchset) representing the |
|
** current contents of the changegroup. If the inputs to the changegroup |
|
** were themselves changesets, the output is a changeset. Or, if the |
|
** inputs were patchsets, the output is also a patchset. |
|
** |
|
** As with the output of the sqlite3session_changeset() and |
|
** sqlite3session_patchset() functions, all changes related to a single |
|
** table are grouped together in the output of this function. Tables appear |
|
** in the same order as for the very first changeset added to the changegroup. |
|
** If the second or subsequent changesets added to the changegroup contain |
|
** changes for tables that do not appear in the first changeset, they are |
|
** appended onto the end of the output changeset, again in the order in |
|
** which they are first encountered. |
|
** |
|
** If an error occurs, an SQLite error code is returned and the output |
|
** variables (*pnData) and (*ppData) are set to 0. Otherwise, SQLITE_OK |
|
** is returned and the output variables are set to the size of and a |
|
** pointer to the output buffer, respectively. In this case it is the |
|
** responsibility of the caller to eventually free the buffer using a |
|
** call to sqlite3_free(). |
|
*/ |
|
int sqlite3changegroup_output( |
|
sqlite3_changegroup*, |
|
int *pnData, /* OUT: Size of output buffer in bytes */ |
|
void **ppData /* OUT: Pointer to output buffer */ |
|
); |
|
|
|
/* |
|
** CAPI3REF: Delete A Changegroup Object |
|
*/ |
|
void sqlite3changegroup_delete(sqlite3_changegroup*); |
|
|
|
/* |
|
** CAPI3REF: Apply A Changeset To A Database |
|
** |
|
** Apply a changeset to a database. This function attempts to update the |
|
** "main" database attached to handle db with the changes found in the |
|
** changeset passed via the second and third arguments. |
|
** |
|
** The fourth argument (xFilter) passed to this function is the "filter |
|
** callback". If it is not NULL, then for each table affected by at least one |
|
** change in the changeset, the filter callback is invoked with |
|
** the table name as the second argument, and a copy of the context pointer |
|
** passed as the sixth argument to this function as the first. If the "filter |
|
** callback" returns zero, then no attempt is made to apply any changes to |
|
** the table. Otherwise, if the return value is non-zero or the xFilter |
|
** argument to this function is NULL, all changes related to the table are |
|
** attempted. |
|
** |
|
** For each table that is not excluded by the filter callback, this function |
|
** tests that the target database contains a compatible table. A table is |
|
** considered compatible if all of the following are true: |
|
** |
|
** <ul> |
|
** <li> The table has the same name as the name recorded in the |
|
** changeset, and |
|
** <li> The table has the same number of columns as recorded in the |
|
** changeset, and |
|
** <li> The table has primary key columns in the same position as |
|
** recorded in the changeset. |
|
** </ul> |
|
** |
|
** If there is no compatible table, it is not an error, but none of the |
|
** changes associated with the table are applied. A warning message is issued |
|
** via the sqlite3_log() mechanism with the error code SQLITE_SCHEMA. At most |
|
** one such warning is issued for each table in the changeset. |
|
** |
|
** For each change for which there is a compatible table, an attempt is made |
|
** to modify the table contents according to the UPDATE, INSERT or DELETE |
|
** change. If a change cannot be applied cleanly, the conflict handler |
|
** function passed as the fifth argument to sqlite3changeset_apply() may be |
|
** invoked. A description of exactly when the conflict handler is invoked for |
|
** each type of change is below. |
|
** |
|
** Unlike the xFilter argument, xConflict may not be passed NULL. The results |
|
** of passing anything other than a valid function pointer as the xConflict |
|
** argument are undefined. |
|
** |
|
** Each time the conflict handler function is invoked, it must return one |
|
** of [SQLITE_CHANGESET_OMIT], [SQLITE_CHANGESET_ABORT] or |
|
** [SQLITE_CHANGESET_REPLACE]. SQLITE_CHANGESET_REPLACE may only be returned |
|
** if the second argument passed to the conflict handler is either |
|
** SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If the conflict-handler |
|
** returns an illegal value, any changes already made are rolled back and |
|
** the call to sqlite3changeset_apply() returns SQLITE_MISUSE. Different |
|
** actions are taken by sqlite3changeset_apply() depending on the value |
|
** returned by each invocation of the conflict-handler function. Refer to |
|
** the documentation for the three |
|
** [SQLITE_CHANGESET_OMIT|available return values] for details. |
|
** |
|
** <dl> |
|
** <dt>DELETE Changes<dd> |
|
** For each DELETE change, this function checks if the target database |
|
** contains a row with the same primary key value (or values) as the |
|
** original row values stored in the changeset. If it does, and the values |
|
** stored in all non-primary key columns also match the values stored in |
|
** the changeset the row is deleted from the target database. |
|
** |
|
** If a row with matching primary key values is found, but one or more of |
|
** the non-primary key fields contains a value different from the original |
|
** row value stored in the changeset, the conflict-handler function is |
|
** invoked with [SQLITE_CHANGESET_DATA] as the second argument. |
|
** |
|
** If no row with matching primary key values is found in the database, |
|
** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND] |
|
** passed as the second argument. |
|
** |
|
** If the DELETE operation is attempted, but SQLite returns SQLITE_CONSTRAINT |
|
** (which can only happen if a foreign key constraint is violated), the |
|
** conflict-handler function is invoked with [SQLITE_CHANGESET_CONSTRAINT] |
|
** passed as the second argument. This includes the case where the DELETE |
|
** operation is attempted because an earlier call to the conflict handler |
|
** function returned [SQLITE_CHANGESET_REPLACE]. |
|
** |
|
** <dt>INSERT Changes<dd> |
|
** For each INSERT change, an attempt is made to insert the new row into |
|
** the database. |
|
** |
|
** If the attempt to insert the row fails because the database already |
|
** contains a row with the same primary key values, the conflict handler |
|
** function is invoked with the second argument set to |
|
** [SQLITE_CHANGESET_CONFLICT]. |
|
** |
|
** If the attempt to insert the row fails because of some other constraint |
|
** violation (e.g. NOT NULL or UNIQUE), the conflict handler function is |
|
** invoked with the second argument set to [SQLITE_CHANGESET_CONSTRAINT]. |
|
** This includes the case where the INSERT operation is re-attempted because |
|
** an earlier call to the conflict handler function returned |
|
** [SQLITE_CHANGESET_REPLACE]. |
|
** |
|
** <dt>UPDATE Changes<dd> |
|
** For each UPDATE change, this function checks if the target database |
|
** contains a row with the same primary key value (or values) as the |
|
** original row values stored in the changeset. If it does, and the values |
|
** stored in all non-primary key columns also match the values stored in |
|
** the changeset the row is updated within the target database. |
|
** |
|
** If a row with matching primary key values is found, but one or more of |
|
** the non-primary key fields contains a value different from an original |
|
** row value stored in the changeset, the conflict-handler function is |
|
** invoked with [SQLITE_CHANGESET_DATA] as the second argument. Since |
|
** UPDATE changes only contain values for non-primary key fields that are |
|
** to be modified, only those fields need to match the original values to |
|
** avoid the SQLITE_CHANGESET_DATA conflict-handler callback. |
|
** |
|
** If no row with matching primary key values is found in the database, |
|
** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND] |
|
** passed as the second argument. |
|
** |
|
** If the UPDATE operation is attempted, but SQLite returns |
|
** SQLITE_CONSTRAINT, the conflict-handler function is invoked with |
|
** [SQLITE_CHANGESET_CONSTRAINT] passed as the second argument. |
|
** This includes the case where the UPDATE operation is attempted after |
|
** an earlier call to the conflict handler function returned |
|
** [SQLITE_CHANGESET_REPLACE]. |
|
** </dl> |
|
** |
|
** It is safe to execute SQL statements, including those that write to the |
|
** table that the callback related to, from within the xConflict callback. |
|
** This can be used to further customize the applications conflict |
|
** resolution strategy. |
|
** |
|
** All changes made by this function are enclosed in a savepoint transaction. |
|
** If any other error (aside from a constraint failure when attempting to |
|
** write to the target database) occurs, then the savepoint transaction is |
|
** rolled back, restoring the target database to its original state, and an |
|
** SQLite error code returned. |
|
*/ |
|
int sqlite3changeset_apply( |
|
sqlite3 *db, /* Apply change to "main" db of this handle */ |
|
int nChangeset, /* Size of changeset in bytes */ |
|
void *pChangeset, /* Changeset blob */ |
|
int(*xFilter)( |
|
void *pCtx, /* Copy of sixth arg to _apply() */ |
|
const char *zTab /* Table name */ |
|
), |
|
int(*xConflict)( |
|
void *pCtx, /* Copy of sixth arg to _apply() */ |
|
int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ |
|
sqlite3_changeset_iter *p /* Handle describing change and conflict */ |
|
), |
|
void *pCtx /* First argument passed to xConflict */ |
|
); |
|
|
|
/* |
|
** CAPI3REF: Constants Passed To The Conflict Handler |
|
** |
|
** Values that may be passed as the second argument to a conflict-handler. |
|
** |
|
** <dl> |
|
** <dt>SQLITE_CHANGESET_DATA<dd> |
|
** The conflict handler is invoked with CHANGESET_DATA as the second argument |
|
** when processing a DELETE or UPDATE change if a row with the required |
|
** PRIMARY KEY fields is present in the database, but one or more other |
|
** (non primary-key) fields modified by the update do not contain the |
|
** expected "before" values. |
|
** |
|
** The conflicting row, in this case, is the database row with the matching |
|
** primary key. |
|
** |
|
** <dt>SQLITE_CHANGESET_NOTFOUND<dd> |
|
** The conflict handler is invoked with CHANGESET_NOTFOUND as the second |
|
** argument when processing a DELETE or UPDATE change if a row with the |
|
** required PRIMARY KEY fields is not present in the database. |
|
** |
|
** There is no conflicting row in this case. The results of invoking the |
|
** sqlite3changeset_conflict() API are undefined. |
|
** |
|
** <dt>SQLITE_CHANGESET_CONFLICT<dd> |
|
** CHANGESET_CONFLICT is passed as the second argument to the conflict |
|
** handler while processing an INSERT change if the operation would result |
|
** in duplicate primary key values. |
|
** |
|
** The conflicting row in this case is the database row with the matching |
|
** primary key. |
|
** |
|
** <dt>SQLITE_CHANGESET_FOREIGN_KEY<dd> |
|
** If foreign key handling is enabled, and applying a changeset leaves the |
|
** database in a state containing foreign key violations, the conflict |
|
** handler is invoked with CHANGESET_FOREIGN_KEY as the second argument |
|
** exactly once before the changeset is committed. If the conflict handler |
|
** returns CHANGESET_OMIT, the changes, including those that caused the |
|
** foreign key constraint violation, are committed. Or, if it returns |
|
** CHANGESET_ABORT, the changeset is rolled back. |
|
** |
|
** No current or conflicting row information is provided. The only function |
|
** it is possible to call on the supplied sqlite3_changeset_iter handle |
|
** is sqlite3changeset_fk_conflicts(). |
|
** |
|
** <dt>SQLITE_CHANGESET_CONSTRAINT<dd> |
|
** If any other constraint violation occurs while applying a change (i.e. |
|
** a UNIQUE, CHECK or NOT NULL constraint), the conflict handler is |
|
** invoked with CHANGESET_CONSTRAINT as the second argument. |
|
** |
|
** There is no conflicting row in this case. The results of invoking the |
|
** sqlite3changeset_conflict() API are undefined. |
|
** |
|
** </dl> |
|
*/ |
|
#define SQLITE_CHANGESET_DATA 1 |
|
#define SQLITE_CHANGESET_NOTFOUND 2 |
|
#define SQLITE_CHANGESET_CONFLICT 3 |
|
#define SQLITE_CHANGESET_CONSTRAINT 4 |
|
#define SQLITE_CHANGESET_FOREIGN_KEY 5 |
|
|
|
/* |
|
** CAPI3REF: Constants Returned By The Conflict Handler |
|
** |
|
** A conflict handler callback must return one of the following three values. |
|
** |
|
** <dl> |
|
** <dt>SQLITE_CHANGESET_OMIT<dd> |
|
** If a conflict handler returns this value no special action is taken. The |
|
** change that caused the conflict is not applied. The session module |
|
** continues to the next change in the changeset. |
|
** |
|
** <dt>SQLITE_CHANGESET_REPLACE<dd> |
|
** This value may only be returned if the second argument to the conflict |
|
** handler was SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If this |
|
** is not the case, any changes applied so far are rolled back and the |
|
** call to sqlite3changeset_apply() returns SQLITE_MISUSE. |
|
** |
|
** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_DATA conflict |
|
** handler, then the conflicting row is either updated or deleted, depending |
|
** on the type of change. |
|
** |
|
** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_CONFLICT conflict |
|
** handler, then the conflicting row is removed from the database and a |
|
** second attempt to apply the change is made. If this second attempt fails, |
|
** the original row is restored to the database before continuing. |
|
** |
|
** <dt>SQLITE_CHANGESET_ABORT<dd> |
|
** If this value is returned, any changes applied so far are rolled back |
|
** and the call to sqlite3changeset_apply() returns SQLITE_ABORT. |
|
** </dl> |
|
*/ |
|
#define SQLITE_CHANGESET_OMIT 0 |
|
#define SQLITE_CHANGESET_REPLACE 1 |
|
#define SQLITE_CHANGESET_ABORT 2 |
|
|
|
/* |
|
** CAPI3REF: Streaming Versions of API functions. |
|
** |
|
** The six streaming API xxx_strm() functions serve similar purposes to the |
|
** corresponding non-streaming API functions: |
|
** |
|
** <table border=1 style="margin-left:8ex;margin-right:8ex"> |
|
** <tr><th>Streaming function<th>Non-streaming equivalent</th> |
|
** <tr><td>sqlite3changeset_apply_str<td>[sqlite3changeset_apply] |
|
** <tr><td>sqlite3changeset_concat_str<td>[sqlite3changeset_concat] |
|
** <tr><td>sqlite3changeset_invert_str<td>[sqlite3changeset_invert] |
|
** <tr><td>sqlite3changeset_start_str<td>[sqlite3changeset_start] |
|
** <tr><td>sqlite3session_changeset_str<td>[sqlite3session_changeset] |
|
** <tr><td>sqlite3session_patchset_str<td>[sqlite3session_patchset] |
|
** </table> |
|
** |
|
** Non-streaming functions that accept changesets (or patchsets) as input |
|
** require that the entire changeset be stored in a single buffer in memory. |
|
** Similarly, those that return a changeset or patchset do so by returning |
|
** a pointer to a single large buffer allocated using sqlite3_malloc(). |
|
** Normally this is convenient. However, if an application running in a |
|
** low-memory environment is required to handle very large changesets, the |
|
** large contiguous memory allocations required can become onerous. |
|
** |
|
** In order to avoid this problem, instead of a single large buffer, input |
|
** is passed to a streaming API functions by way of a callback function that |
|
** the sessions module invokes to incrementally request input data as it is |
|
** required. In all cases, a pair of API function parameters such as |
|
** |
|
** <pre> |
|
** int nChangeset, |
|
** void *pChangeset, |
|
** </pre> |
|
** |
|
** Is replaced by: |
|
** |
|
** <pre> |
|
** int (*xInput)(void *pIn, void *pData, int *pnData), |
|
** void *pIn, |
|
** </pre> |
|
** |
|
** Each time the xInput callback is invoked by the sessions module, the first |
|
** argument passed is a copy of the supplied pIn context pointer. The second |
|
** argument, pData, points to a buffer (*pnData) bytes in size. Assuming no |
|
** error occurs the xInput method should copy up to (*pnData) bytes of data |
|
** into the buffer and set (*pnData) to the actual number of bytes copied |
|
** before returning SQLITE_OK. If the input is completely exhausted, (*pnData) |
|
** should be set to zero to indicate this. Or, if an error occurs, an SQLite |
|
** error code should be returned. In all cases, if an xInput callback returns |
|
** an error, all processing is abandoned and the streaming API function |
|
** returns a copy of the error code to the caller. |
|
** |
|
** In the case of sqlite3changeset_start_strm(), the xInput callback may be |
|
** invoked by the sessions module at any point during the lifetime of the |
|
** iterator. If such an xInput callback returns an error, the iterator enters |
|
** an error state, whereby all subsequent calls to iterator functions |
|
** immediately fail with the same error code as returned by xInput. |
|
** |
|
** Similarly, streaming API functions that return changesets (or patchsets) |
|
** return them in chunks by way of a callback function instead of via a |
|
** pointer to a single large buffer. In this case, a pair of parameters such |
|
** as: |
|
** |
|
** <pre> |
|
** int *pnChangeset, |
|
** void **ppChangeset, |
|
** </pre> |
|
** |
|
** Is replaced by: |
|
** |
|
** <pre> |
|
** int (*xOutput)(void *pOut, const void *pData, int nData), |
|
** void *pOut |
|
** </pre> |
|
** |
|
** The xOutput callback is invoked zero or more times to return data to |
|
** the application. The first parameter passed to each call is a copy of the |
|
** pOut pointer supplied by the application. The second parameter, pData, |
|
** points to a buffer nData bytes in size containing the chunk of output |
|
** data being returned. If the xOutput callback successfully processes the |
|
** supplied data, it should return SQLITE_OK to indicate success. Otherwise, |
|
** it should return some other SQLite error code. In this case processing |
|
** is immediately abandoned and the streaming API function returns a copy |
|
** of the xOutput error code to the application. |
|
** |
|
** The sessions module never invokes an xOutput callback with the third |
|
** parameter set to a value less than or equal to zero. Other than this, |
|
** no guarantees are made as to the size of the chunks of data returned. |
|
*/ |
|
int sqlite3changeset_apply_strm( |
|
sqlite3 *db, /* Apply change to "main" db of this handle */ |
|
int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */ |
|
void *pIn, /* First arg for xInput */ |
|
int(*xFilter)( |
|
void *pCtx, /* Copy of sixth arg to _apply() */ |
|
const char *zTab /* Table name */ |
|
), |
|
int(*xConflict)( |
|
void *pCtx, /* Copy of sixth arg to _apply() */ |
|
int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ |
|
sqlite3_changeset_iter *p /* Handle describing change and conflict */ |
|
), |
|
void *pCtx /* First argument passed to xConflict */ |
|
); |
|
int sqlite3changeset_concat_strm( |
|
int (*xInputA)(void *pIn, void *pData, int *pnData), |
|
void *pInA, |
|
int (*xInputB)(void *pIn, void *pData, int *pnData), |
|
void *pInB, |
|
int (*xOutput)(void *pOut, const void *pData, int nData), |
|
void *pOut |
|
); |
|
int sqlite3changeset_invert_strm( |
|
int (*xInput)(void *pIn, void *pData, int *pnData), |
|
void *pIn, |
|
int (*xOutput)(void *pOut, const void *pData, int nData), |
|
void *pOut |
|
); |
|
int sqlite3changeset_start_strm( |
|
sqlite3_changeset_iter **pp, |
|
int (*xInput)(void *pIn, void *pData, int *pnData), |
|
void *pIn |
|
); |
|
int sqlite3session_changeset_strm( |
|
sqlite3_session *pSession, |
|
int (*xOutput)(void *pOut, const void *pData, int nData), |
|
void *pOut |
|
); |
|
int sqlite3session_patchset_strm( |
|
sqlite3_session *pSession, |
|
int (*xOutput)(void *pOut, const void *pData, int nData), |
|
void *pOut |
|
); |
|
int sqlite3changegroup_add_strm(sqlite3_changegroup*, |
|
int (*xInput)(void *pIn, void *pData, int *pnData), |
|
void *pIn |
|
); |
|
int sqlite3changegroup_output_strm(sqlite3_changegroup*, |
|
int (*xOutput)(void *pOut, const void *pData, int nData), |
|
void *pOut |
|
); |
|
|
|
|
|
/* |
|
** Make sure we can call this stuff from C++. |
|
*/ |
|
#ifdef __cplusplus |
|
} |
|
#endif |
|
|
|
#endif /* !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) */ |
|
|
|
/******** End of sqlite3session.h *********/ |
|
/******** Begin file fts5.h *********/ |
|
/* |
|
** 2014 May 31 |
|
** |
|
** The author disclaims copyright to this source code. In place of |
|
** a legal notice, here is a blessing: |
|
** |
|
** May you do good and not evil. |
|
** May you find forgiveness for yourself and forgive others. |
|
** May you share freely, never taking more than you give. |
|
** |
|
****************************************************************************** |
|
** |
|
** Interfaces to extend FTS5. Using the interfaces defined in this file, |
|
** FTS5 may be extended with: |
|
** |
|
** * custom tokenizers, and |
|
** * custom auxiliary functions. |
|
*/ |
|
|
|
|
|
#ifndef _FTS5_H |
|
#define _FTS5_H |
|
|
|
|
|
#ifdef __cplusplus |
|
extern "C" { |
|
#endif |
|
|
|
/************************************************************************* |
|
** CUSTOM AUXILIARY FUNCTIONS |
|
** |
|
** Virtual table implementations may overload SQL functions by implementing |
|
** the sqlite3_module.xFindFunction() method. |
|
*/ |
|
|
|
typedef struct Fts5ExtensionApi Fts5ExtensionApi; |
|
typedef struct Fts5Context Fts5Context; |
|
typedef struct Fts5PhraseIter Fts5PhraseIter; |
|
|
|
typedef void (*fts5_extension_function)( |
|
const Fts5ExtensionApi *pApi, /* API offered by current FTS version */ |
|
Fts5Context *pFts, /* First arg to pass to pApi functions */ |
|
sqlite3_context *pCtx, /* Context for returning result/error */ |
|
int nVal, /* Number of values in apVal[] array */ |
|
sqlite3_value **apVal /* Array of trailing arguments */ |
|
); |
|
|
|
struct Fts5PhraseIter { |
|
const unsigned char *a; |
|
const unsigned char *b; |
|
}; |
|
|
|
/* |
|
** EXTENSION API FUNCTIONS |
|
** |
|
** xUserData(pFts): |
|
** Return a copy of the context pointer the extension function was |
|
** registered with. |
|
** |
|
** xColumnTotalSize(pFts, iCol, pnToken): |
|
** If parameter iCol is less than zero, set output variable *pnToken |
|
** to the total number of tokens in the FTS5 table. Or, if iCol is |
|
** non-negative but less than the number of columns in the table, return |
|
** the total number of tokens in column iCol, considering all rows in |
|
** the FTS5 table. |
|
** |
|
** If parameter iCol is greater than or equal to the number of columns |
|
** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g. |
|
** an OOM condition or IO error), an appropriate SQLite error code is |
|
** returned. |
|
** |
|
** xColumnCount(pFts): |
|
** Return the number of columns in the table. |
|
** |
|
** xColumnSize(pFts, iCol, pnToken): |
|
** If parameter iCol is less than zero, set output variable *pnToken |
|
** to the total number of tokens in the current row. Or, if iCol is |
|
** non-negative but less than the number of columns in the table, set |
|
** *pnToken to the number of tokens in column iCol of the current row. |
|
** |
|
** If parameter iCol is greater than or equal to the number of columns |
|
** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g. |
|
** an OOM condition or IO error), an appropriate SQLite error code is |
|
** returned. |
|
** |
|
** This function may be quite inefficient if used with an FTS5 table |
|
** created with the "columnsize=0" option. |
|
** |
|
** xColumnText: |
|
** This function attempts to retrieve the text of column iCol of the |
|
** current document. If successful, (*pz) is set to point to a buffer |
|
** containing the text in utf-8 encoding, (*pn) is set to the size in bytes |
|
** (not characters) of the buffer and SQLITE_OK is returned. Otherwise, |
|
** if an error occurs, an SQLite error code is returned and the final values |
|
** of (*pz) and (*pn) are undefined. |
|
** |
|
** xPhraseCount: |
|
** Returns the number of phrases in the current query expression. |
|
** |
|
** xPhraseSize: |
|
** Returns the number of tokens in phrase iPhrase of the query. Phrases |
|
** are numbered starting from zero. |
|
** |
|
** xInstCount: |
|
** Set *pnInst to the total number of occurrences of all phrases within |
|
** the query within the current row. Return SQLITE_OK if successful, or |
|
** an error code (i.e. SQLITE_NOMEM) if an error occurs. |
|
** |
|
** This API can be quite slow if used with an FTS5 table created with the |
|
** "detail=none" or "detail=column" option. If the FTS5 table is created |
|
** with either "detail=none" or "detail=column" and "content=" option |
|
** (i.e. if it is a contentless table), then this API always returns 0. |
|
** |
|
** xInst: |
|
** Query for the details of phrase match iIdx within the current row. |
|
** Phrase matches are numbered starting from zero, so the iIdx argument |
|
** should be greater than or equal to zero and smaller than the value |
|
** output by xInstCount(). |
|
** |
|
** Usually, output parameter *piPhrase is set to the phrase number, *piCol |
|
** to the column in which it occurs and *piOff the token offset of the |
|
** first token of the phrase. The exception is if the table was created |
|
** with the offsets=0 option specified. In this case *piOff is always |
|
** set to -1. |
|
** |
|
** Returns SQLITE_OK if successful, or an error code (i.e. SQLITE_NOMEM) |
|
** if an error occurs. |
|
** |
|
** This API can be quite slow if used with an FTS5 table created with the |
|
** "detail=none" or "detail=column" option. |
|
** |
|
** xRowid: |
|
** Returns the rowid of the current row. |
|
** |
|
** xTokenize: |
|
** Tokenize text using the tokenizer belonging to the FTS5 table. |
|
** |
|
** xQueryPhrase(pFts5, iPhrase, pUserData, xCallback): |
|
** This API function is used to query the FTS table for phrase iPhrase |
|
** of the current query. Specifically, a query equivalent to: |
|
** |
|
** ... FROM ftstable WHERE ftstable MATCH $p ORDER BY rowid |
|
** |
|
** with $p set to a phrase equivalent to the phrase iPhrase of the |
|
** current query is executed. Any column filter that applies to |
|
** phrase iPhrase of the current query is included in $p. For each |
|
** row visited, the callback function passed as the fourth argument |
|
** is invoked. The context and API objects passed to the callback |
|
** function may be used to access the properties of each matched row. |
|
** Invoking Api.xUserData() returns a copy of the pointer passed as |
|
** the third argument to pUserData. |
|
** |
|
** If the callback function returns any value other than SQLITE_OK, the |
|
** query is abandoned and the xQueryPhrase function returns immediately. |
|
** If the returned value is SQLITE_DONE, xQueryPhrase returns SQLITE_OK. |
|
** Otherwise, the error code is propagated upwards. |
|
** |
|
** If the query runs to completion without incident, SQLITE_OK is returned. |
|
** Or, if some error occurs before the query completes or is aborted by |
|
** the callback, an SQLite error code is returned. |
|
** |
|
** |
|
** xSetAuxdata(pFts5, pAux, xDelete) |
|
** |
|
** Save the pointer passed as the second argument as the extension functions |
|
** "auxiliary data". The pointer may then be retrieved by the current or any |
|
** future invocation of the same fts5 extension function made as part of |
|
** of the same MATCH query using the xGetAuxdata() API. |
|
** |
|
** Each extension function is allocated a single auxiliary data slot for |
|
** each FTS query (MATCH expression). If the extension function is invoked |
|
** more than once for a single FTS query, then all invocations share a |
|
** single auxiliary data context. |
|
** |
|
** If there is already an auxiliary data pointer when this function is |
|
** invoked, then it is replaced by the new pointer. If an xDelete callback |
|
** was specified along with the original pointer, it is invoked at this |
|
** point. |
|
** |
|
** The xDelete callback, if one is specified, is also invoked on the |
|
** auxiliary data pointer after the FTS5 query has finished. |
|
** |
|
** If an error (e.g. an OOM condition) occurs within this function, an |
|
** the auxiliary data is set to NULL and an error code returned. If the |
|
** xDelete parameter was not NULL, it is invoked on the auxiliary data |
|
** pointer before returning. |
|
** |
|
** |
|
** xGetAuxdata(pFts5, bClear) |
|
** |
|
** Returns the current auxiliary data pointer for the fts5 extension |
|
** function. See the xSetAuxdata() method for details. |
|
** |
|
** If the bClear argument is non-zero, then the auxiliary data is cleared |
|
** (set to NULL) before this function returns. In this case the xDelete, |
|
** if any, is not invoked. |
|
** |
|
** |
|
** xRowCount(pFts5, pnRow) |
|
** |
|
** This function is used to retrieve the total number of rows in the table. |
|
** In other words, the same value that would be returned by: |
|
** |
|
** SELECT count(*) FROM ftstable; |
|
** |
|
** xPhraseFirst() |
|
** This function is used, along with type Fts5PhraseIter and the xPhraseNext |
|
** method, to iterate through all instances of a single query phrase within |
|
** the current row. This is the same information as is accessible via the |
|
** xInstCount/xInst APIs. While the xInstCount/xInst APIs are more convenient |
|
** to use, this API may be faster under some circumstances. To iterate |
|
** through instances of phrase iPhrase, use the following code: |
|
** |
|
** Fts5PhraseIter iter; |
|
** int iCol, iOff; |
|
** for(pApi->xPhraseFirst(pFts, iPhrase, &iter, &iCol, &iOff); |
|
** iCol>=0; |
|
** pApi->xPhraseNext(pFts, &iter, &iCol, &iOff) |
|
** ){ |
|
** // An instance of phrase iPhrase at offset iOff of column iCol |
|
** } |
|
** |
|
** The Fts5PhraseIter structure is defined above. Applications should not |
|
** modify this structure directly - it should only be used as shown above |
|
** with the xPhraseFirst() and xPhraseNext() API methods (and by |
|
** xPhraseFirstColumn() and xPhraseNextColumn() as illustrated below). |
|
** |
|
** This API can be quite slow if used with an FTS5 table created with the |
|
** "detail=none" or "detail=column" option. If the FTS5 table is created |
|
** with either "detail=none" or "detail=column" and "content=" option |
|
** (i.e. if it is a contentless table), then this API always iterates |
|
** through an empty set (all calls to xPhraseFirst() set iCol to -1). |
|
** |
|
** xPhraseNext() |
|
** See xPhraseFirst above. |
|
** |
|
** xPhraseFirstColumn() |
|
** This function and xPhraseNextColumn() are similar to the xPhraseFirst() |
|
** and xPhraseNext() APIs described above. The difference is that instead |
|
** of iterating through all instances of a phrase in the current row, these |
|
** APIs are used to iterate through the set of columns in the current row |
|
** that contain one or more instances of a specified phrase. For example: |
|
** |
|
** Fts5PhraseIter iter; |
|
** int iCol; |
|
** for(pApi->xPhraseFirstColumn(pFts, iPhrase, &iter, &iCol); |
|
** iCol>=0; |
|
** pApi->xPhraseNextColumn(pFts, &iter, &iCol) |
|
** ){ |
|
** // Column iCol contains at least one instance of phrase iPhrase |
|
** } |
|
** |
|
** This API can be quite slow if used with an FTS5 table created with the |
|
** "detail=none" option. If the FTS5 table is created with either |
|
** "detail=none" "content=" option (i.e. if it is a contentless table), |
|
** then this API always iterates through an empty set (all calls to |
|
** xPhraseFirstColumn() set iCol to -1). |
|
** |
|
** The information accessed using this API and its companion |
|
** xPhraseFirstColumn() may also be obtained using xPhraseFirst/xPhraseNext |
|
** (or xInst/xInstCount). The chief advantage of this API is that it is |
|
** significantly more efficient than those alternatives when used with |
|
** "detail=column" tables. |
|
** |
|
** xPhraseNextColumn() |
|
** See xPhraseFirstColumn above. |
|
*/ |
|
struct Fts5ExtensionApi { |
|
int iVersion; /* Currently always set to 3 */ |
|
|
|
void *(*xUserData)(Fts5Context*); |
|
|
|
int (*xColumnCount)(Fts5Context*); |
|
int (*xRowCount)(Fts5Context*, sqlite3_int64 *pnRow); |
|
int (*xColumnTotalSize)(Fts5Context*, int iCol, sqlite3_int64 *pnToken); |
|
|
|
int (*xTokenize)(Fts5Context*, |
|
const char *pText, int nText, /* Text to tokenize */ |
|
void *pCtx, /* Context passed to xToken() */ |
|
int (*xToken)(void*, int, const char*, int, int, int) /* Callback */ |
|
); |
|
|
|
int (*xPhraseCount)(Fts5Context*); |
|
int (*xPhraseSize)(Fts5Context*, int iPhrase); |
|
|
|
int (*xInstCount)(Fts5Context*, int *pnInst); |
|
int (*xInst)(Fts5Context*, int iIdx, int *piPhrase, int *piCol, int *piOff); |
|
|
|
sqlite3_int64 (*xRowid)(Fts5Context*); |
|
int (*xColumnText)(Fts5Context*, int iCol, const char **pz, int *pn); |
|
int (*xColumnSize)(Fts5Context*, int iCol, int *pnToken); |
|
|
|
int (*xQueryPhrase)(Fts5Context*, int iPhrase, void *pUserData, |
|
int(*)(const Fts5ExtensionApi*,Fts5Context*,void*) |
|
); |
|
int (*xSetAuxdata)(Fts5Context*, void *pAux, void(*xDelete)(void*)); |
|
void *(*xGetAuxdata)(Fts5Context*, int bClear); |
|
|
|
int (*xPhraseFirst)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*, int*); |
|
void (*xPhraseNext)(Fts5Context*, Fts5PhraseIter*, int *piCol, int *piOff); |
|
|
|
int (*xPhraseFirstColumn)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*); |
|
void (*xPhraseNextColumn)(Fts5Context*, Fts5PhraseIter*, int *piCol); |
|
}; |
|
|
|
/* |
|
** CUSTOM AUXILIARY FUNCTIONS |
|
*************************************************************************/ |
|
|
|
/************************************************************************* |
|
** CUSTOM TOKENIZERS |
|
** |
|
** Applications may also register custom tokenizer types. A tokenizer |
|
** is registered by providing fts5 with a populated instance of the |
|
** following structure. All structure methods must be defined, setting |
|
** any member of the fts5_tokenizer struct to NULL leads to undefined |
|
** behaviour. The structure methods are expected to function as follows: |
|
** |
|
** xCreate: |
|
** This function is used to allocate and initialize a tokenizer instance. |
|
** A tokenizer instance is required to actually tokenize text. |
|
** |
|
** The first argument passed to this function is a copy of the (void*) |
|
** pointer provided by the application when the fts5_tokenizer object |
|
** was registered with FTS5 (the third argument to xCreateTokenizer()). |
|
** The second and third arguments are an array of nul-terminated strings |
|
** containing the tokenizer arguments, if any, specified following the |
|
** tokenizer name as part of the CREATE VIRTUAL TABLE statement used |
|
** to create the FTS5 table. |
|
** |
|
** The final argument is an output variable. If successful, (*ppOut) |
|
** should be set to point to the new tokenizer handle and SQLITE_OK |
|
** returned. If an error occurs, some value other than SQLITE_OK should |
|
** be returned. In this case, fts5 assumes that the final value of *ppOut |
|
** is undefined. |
|
** |
|
** xDelete: |
|
** This function is invoked to delete a tokenizer handle previously |
|
** allocated using xCreate(). Fts5 guarantees that this function will |
|
** be invoked exactly once for each successful call to xCreate(). |
|
** |
|
** xTokenize: |
|
** This function is expected to tokenize the nText byte string indicated |
|
** by argument pText. pText may or may not be nul-terminated. The first |
|
** argument passed to this function is a pointer to an Fts5Tokenizer object |
|
** returned by an earlier call to xCreate(). |
|
** |
|
** The second argument indicates the reason that FTS5 is requesting |
|
** tokenization of the supplied text. This is always one of the following |
|
** four values: |
|
** |
|
** <ul><li> <b>FTS5_TOKENIZE_DOCUMENT</b> - A document is being inserted into |
|
** or removed from the FTS table. The tokenizer is being invoked to |
|
** determine the set of tokens to add to (or delete from) the |
|
** FTS index. |
|
** |
|
** <li> <b>FTS5_TOKENIZE_QUERY</b> - A MATCH query is being executed |
|
** against the FTS index. The tokenizer is being called to tokenize |
|
** a bareword or quoted string specified as part of the query. |
|
** |
|
** <li> <b>(FTS5_TOKENIZE_QUERY | FTS5_TOKENIZE_PREFIX)</b> - Same as |
|
** FTS5_TOKENIZE_QUERY, except that the bareword or quoted string is |
|
** followed by a "*" character, indicating that the last token |
|
** returned by the tokenizer will be treated as a token prefix. |
|
** |
|
** <li> <b>FTS5_TOKENIZE_AUX</b> - The tokenizer is being invoked to |
|
** satisfy an fts5_api.xTokenize() request made by an auxiliary |
|
** function. Or an fts5_api.xColumnSize() request made by the same |
|
** on a columnsize=0 database. |
|
** </ul> |
|
** |
|
** For each token in the input string, the supplied callback xToken() must |
|
** be invoked. The first argument to it should be a copy of the pointer |
|
** passed as the second argument to xTokenize(). The third and fourth |
|
** arguments are a pointer to a buffer containing the token text, and the |
|
** size of the token in bytes. The 4th and 5th arguments are the byte offsets |
|
** of the first byte of and first byte immediately following the text from |
|
** which the token is derived within the input. |
|
** |
|
** The second argument passed to the xToken() callback ("tflags") should |
|
** normally be set to 0. The exception is if the tokenizer supports |
|
** synonyms. In this case see the discussion below for details. |
|
** |
|
** FTS5 assumes the xToken() callback is invoked for each token in the |
|
** order that they occur within the input text. |
|
** |
|
** If an xToken() callback returns any value other than SQLITE_OK, then |
|
** the tokenization should be abandoned and the xTokenize() method should |
|
** immediately return a copy of the xToken() return value. Or, if the |
|
** input buffer is exhausted, xTokenize() should return SQLITE_OK. Finally, |
|
** if an error occurs with the xTokenize() implementation itself, it |
|
** may abandon the tokenization and return any error code other than |
|
** SQLITE_OK or SQLITE_DONE. |
|
** |
|
** SYNONYM SUPPORT |
|
** |
|
** Custom tokenizers may also support synonyms. Consider a case in which a |
|
** user wishes to query for a phrase such as "first place". Using the |
|
** built-in tokenizers, the FTS5 query 'first + place' will match instances |
|
** of "first place" within the document set, but not alternative forms |
|
** such as "1st place". In some applications, it would be better to match |
|
** all instances of "first place" or "1st place" regardless of which form |
|
** the user specified in the MATCH query text. |
|
** |
|
** There are several ways to approach this in FTS5: |
|
** |
|
** <ol><li> By mapping all synonyms to a single token. In this case, the |
|
** In the above example, this means that the tokenizer returns the |
|
** same token for inputs "first" and "1st". Say that token is in |
|
** fact "first", so that when the user inserts the document "I won |
|
** 1st place" entries are added to the index for tokens "i", "won", |
|
** "first" and "place". If the user then queries for '1st + place', |
|
** the tokenizer substitutes "first" for "1st" and the query works |
|
** as expected. |
|
** |
|
** <li> By adding multiple synonyms for a single term to the FTS index. |
|
** In this case, when tokenizing query text, the tokenizer may |
|
** provide multiple synonyms for a single term within the document. |
|
** FTS5 then queries the index for each synonym individually. For |
|
** example, faced with the query: |
|
** |
|
** <codeblock> |
|
** ... MATCH 'first place'</codeblock> |
|
** |
|
** the tokenizer offers both "1st" and "first" as synonyms for the |
|
** first token in the MATCH query and FTS5 effectively runs a query |
|
** similar to: |
|
** |
|
** <codeblock> |
|
** ... MATCH '(first OR 1st) place'</codeblock> |
|
** |
|
** except that, for the purposes of auxiliary functions, the query |
|
** still appears to contain just two phrases - "(first OR 1st)" |
|
** being treated as a single phrase. |
|
** |
|
** <li> By adding multiple synonyms for a single term to the FTS index. |
|
** Using this method, when tokenizing document text, the tokenizer |
|
** provides multiple synonyms for each token. So that when a |
|
** document such as "I won first place" is tokenized, entries are |
|
** added to the FTS index for "i", "won", "first", "1st" and |
|
** "place". |
|
** |
|
** This way, even if the tokenizer does not provide synonyms |
|
** when tokenizing query text (it should not - to do would be |
|
** inefficient), it doesn't matter if the user queries for |
|
** 'first + place' or '1st + place', as there are entires in the |
|
** FTS index corresponding to both forms of the first token. |
|
** </ol> |
|
** |
|
** Whether it is parsing document or query text, any call to xToken that |
|
** specifies a <i>tflags</i> argument with the FTS5_TOKEN_COLOCATED bit |
|
** is considered to supply a synonym for the previous token. For example, |
|
** when parsing the document "I won first place", a tokenizer that supports |
|
** synonyms would call xToken() 5 times, as follows: |
|
** |
|
** <codeblock> |
|
** xToken(pCtx, 0, "i", 1, 0, 1); |
|
** xToken(pCtx, 0, "won", 3, 2, 5); |
|
** xToken(pCtx, 0, "first", 5, 6, 11); |
|
** xToken(pCtx, FTS5_TOKEN_COLOCATED, "1st", 3, 6, 11); |
|
** xToken(pCtx, 0, "place", 5, 12, 17); |
|
**</codeblock> |
|
** |
|
** It is an error to specify the FTS5_TOKEN_COLOCATED flag the first time |
|
** xToken() is called. Multiple synonyms may be specified for a single token |
|
** by making multiple calls to xToken(FTS5_TOKEN_COLOCATED) in sequence. |
|
** There is no limit to the number of synonyms that may be provided for a |
|
** single token. |
|
** |
|
** In many cases, method (1) above is the best approach. It does not add |
|
** extra data to the FTS index or require FTS5 to query for multiple terms, |
|
** so it is efficient in terms of disk space and query speed. However, it |
|
** does not support prefix queries very well. If, as suggested above, the |
|
** token "first" is subsituted for "1st" by the tokenizer, then the query: |
|
** |
|
** <codeblock> |
|
** ... MATCH '1s*'</codeblock> |
|
** |
|
** will not match documents that contain the token "1st" (as the tokenizer |
|
** will probably not map "1s" to any prefix of "first"). |
|
** |
|
** For full prefix support, method (3) may be preferred. In this case, |
|
** because the index contains entries for both "first" and "1st", prefix |
|
** queries such as 'fi*' or '1s*' will match correctly. However, because |
|
** extra entries are added to the FTS index, this method uses more space |
|
** within the database. |
|
** |
|
** Method (2) offers a midpoint between (1) and (3). Using this method, |
|
** a query such as '1s*' will match documents that contain the literal |
|
** token "1st", but not "first" (assuming the tokenizer is not able to |
|
** provide synonyms for prefixes). However, a non-prefix query like '1st' |
|
** will match against "1st" and "first". This method does not require |
|
** extra disk space, as no extra entries are added to the FTS index. |
|
** On the other hand, it may require more CPU cycles to run MATCH queries, |
|
** as separate queries of the FTS index are required for each synonym. |
|
** |
|
** When using methods (2) or (3), it is important that the tokenizer only |
|
** provide synonyms when tokenizing document text (method (2)) or query |
|
** text (method (3)), not both. Doing so will not cause any errors, but is |
|
** inefficient. |
|
*/ |
|
typedef struct Fts5Tokenizer Fts5Tokenizer; |
|
typedef struct fts5_tokenizer fts5_tokenizer; |
|
struct fts5_tokenizer { |
|
int (*xCreate)(void*, const char **azArg, int nArg, Fts5Tokenizer **ppOut); |
|
void (*xDelete)(Fts5Tokenizer*); |
|
int (*xTokenize)(Fts5Tokenizer*, |
|
void *pCtx, |
|
int flags, /* Mask of FTS5_TOKENIZE_* flags */ |
|
const char *pText, int nText, |
|
int (*xToken)( |
|
void *pCtx, /* Copy of 2nd argument to xTokenize() */ |
|
int tflags, /* Mask of FTS5_TOKEN_* flags */ |
|
const char *pToken, /* Pointer to buffer containing token */ |
|
int nToken, /* Size of token in bytes */ |
|
int iStart, /* Byte offset of token within input text */ |
|
int iEnd /* Byte offset of end of token within input text */ |
|
) |
|
); |
|
}; |
|
|
|
/* Flags that may be passed as the third argument to xTokenize() */ |
|
#define FTS5_TOKENIZE_QUERY 0x0001 |
|
#define FTS5_TOKENIZE_PREFIX 0x0002 |
|
#define FTS5_TOKENIZE_DOCUMENT 0x0004 |
|
#define FTS5_TOKENIZE_AUX 0x0008 |
|
|
|
/* Flags that may be passed by the tokenizer implementation back to FTS5 |
|
** as the third argument to the supplied xToken callback. */ |
|
#define FTS5_TOKEN_COLOCATED 0x0001 /* Same position as prev. token */ |
|
|
|
/* |
|
** END OF CUSTOM TOKENIZERS |
|
*************************************************************************/ |
|
|
|
/************************************************************************* |
|
** FTS5 EXTENSION REGISTRATION API |
|
*/ |
|
typedef struct fts5_api fts5_api; |
|
struct fts5_api { |
|
int iVersion; /* Currently always set to 2 */ |
|
|
|
/* Create a new tokenizer */ |
|
int (*xCreateTokenizer)( |
|
fts5_api *pApi, |
|
const char *zName, |
|
void *pContext, |
|
fts5_tokenizer *pTokenizer, |
|
void (*xDestroy)(void*) |
|
); |
|
|
|
/* Find an existing tokenizer */ |
|
int (*xFindTokenizer)( |
|
fts5_api *pApi, |
|
const char *zName, |
|
void **ppContext, |
|
fts5_tokenizer *pTokenizer |
|
); |
|
|
|
/* Create a new auxiliary function */ |
|
int (*xCreateFunction)( |
|
fts5_api *pApi, |
|
const char *zName, |
|
void *pContext, |
|
fts5_extension_function xFunction, |
|
void (*xDestroy)(void*) |
|
); |
|
}; |
|
|
|
/* |
|
** END OF REGISTRATION API |
|
*************************************************************************/ |
|
|
|
#ifdef __cplusplus |
|
} /* end of the 'extern "C"' block */ |
|
#endif |
|
|
|
#endif /* _FTS5_H */ |
|
|
|
/******** End of fts5.h *********/ |
|
#else // USE_LIBSQLITE3 |
|
// If users really want to link against the system sqlite3 we |
|
// need to make this file a noop. |
|
#endif |