diff --git a/models/migrations/v18.go b/models/migrations/v18.go
index 1185692ac..839e181f3 100644
--- a/models/migrations/v18.go
+++ b/models/migrations/v18.go
@@ -9,6 +9,10 @@ import (
 )
 
 func cleanUnlinkedWebhookAndHookTasks(x *xorm.Engine) error {
-	_, err := x.Exec(`DELETE FROM webhook WHERE repo_id NOT IN (SELECT id FROM repository);DELETE FROM hook_task WHERE repo_id NOT IN (SELECT id FROM repository);`)
+	_, err := x.Exec(`DELETE FROM webhook WHERE repo_id NOT IN (SELECT id FROM repository);`)
+	if err != nil {
+		return err
+	}
+	_, err = x.Exec(`DELETE FROM hook_task WHERE repo_id NOT IN (SELECT id FROM repository);`)
 	return err
 }