TCL : Commit, Roleback, SavePoint

COMMIT

Permanently saves all changes made in the current transaction, e.g. COMMIT; — after this, the changes cannot be undone with ROLLBACK.

ROLLBACK

Undoes changes made in the current transaction that have not yet been committed, e.g. ROLLBACK; — extremely useful in testing to reset data after a destructive test.

SAVEPOINT

Marks a point within a transaction that you can roll back to without undoing the entire transaction, e.g. SAVEPOINT before_update; ... ROLLBACK TO before_update;

Why Testers Use TCL

Wrapping test data changes in transactions with savepoints lets testers safely experiment with data changes and cleanly revert them afterward, keeping the test environment consistent.