sqlite3_changes

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int sqlite3_changes  
(  
    sqlite3 *  
)  
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int sqlite3_changes (     sqlite3 * )

Remarks

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:

• ^(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.)^

• ^(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.)^

^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.

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.

See also:

• the [sqlite3_total_changes()] interface
• the [count_changes pragma]
• the [changes() SQL function]
• the [data_version pragma]