DB2 Incremental Delete

Mon, 15 Jul 2013 16:40:00 +0000

Ever have to delete a lot of records from a table in DB2 and can’t truncate, but you keep filling the transaction log? One way of solving the problem without having to manually update ranges of values in a where clause is to do an incremental delete in a stored proc. Here’s an example/template to get you started…

WHILE EXISTS ( SELECT ITEM_ID 
		FROM XX.TABLE
		WHERE SOMETHING_NB = 1
		FETCH FIRST 1 ROWS ONLY )
DO
	DELETE FROM 
		(SELECT ROW_NUMBER() OVER() AS ROW_NB
		FROM XX.TABLE
		WHERE SOMETHING_NB = 1
		FETCH FIRST 20000 ROWS ONLY)
	WHERE ROW_NB <= 20000;
	
	IF ((L_SQLCODE_NB <> 0) AND (L_SQLCODE_NB <> 100)) THEN
		SIGNAL SQLSTATE '20003' SET MESSAGE_TEXT = 'Error deleting records';
	END IF; 
	
	COMMIT;
END WHILE;

Stored Proc on MarkJacobsen.net

DB2 Incremental Delete