The TRUNCATE TABLE statement, which has long been available in other DBMS’s such as SQL Server, is now available in DB2. It allows for a quick deletion of all data in a DB2 table, as opposed to a mass DELETE DML statement.
If used with the IMMEDIATE keyword, then the truncate operation is processed immediately and cannot be undone by a subsequent ROLLBACK statement. If the IMMEDIATE keyword is not included in the TRUNCATE TABLE statement, then a ROLLBACK will undo the truncate operation.
There are some restrictions to the use of the TRUNCATE TABLE statement, foremost of which is that a TRUNCATE TABLE statement cannot be issued against a parent table in a referential foreign key constraint. This is regardless of whether the child table in the referential relationship contains any rows.
