SAVEPOINT identifier
ROLLBACK TO SAVEPOINT identifier

Starting from MySQL 4.0.14 and 4.1.1, InnoDB supports the SQL statements SAVEPOINT and ROLLBACK TO SAVEPOINT.

The SAVEPOINT statement sets a named transaction savepoint with a name of identifier. If the current transaction has a savepoint with the same name, the old savepoint is deleted and a new one is set.

The ROLLBACK TO SAVEPOINT statement rolls back a transaction to the named savepoint without terminating the transaction. Modifications that the current transaction made to rows after the savepoint was set are undone in the rollback, but InnoDB does not release the row locks that were stored in memory after the savepoint. (For a new inserted row, the lock information is carried by the transaction ID stored in the row; the lock is not separately stored in memory. In this case, the row lock is released in the undo.) Savepoints that were set at a later time than the named savepoint are deleted.

If the ROLLBACK TO SAVEPOINT statement returns the following error, it means that no savepoint with the specified name exists:

ERROR 1181: Got error 153 during ROLLBACK

All savepoints of the current transaction are deleted if you execute a COMMIT, or a ROLLBACK that does not name a savepoint.