TCL (Transaction Control Language)

TCL is the subset of SQL that manages transactions — COMMIT, ROLLBACK, and SAVEPOINT — controlling when a group of DML changes becomes permanent or is undone.

TCL sits alongside DDL (structure), DML (data), and DCL (permissions) as one of the traditional four categories of SQL statements. COMMIT makes all changes since the last commit permanent and visible to other transactions; ROLLBACK undoes them; SAVEPOINT creates a partial-rollback marker within the transaction.