Backing out database updates dynamically: the ROLL and ROLB commands

When a batch program determines that some of its processing is invalid, the ROLL and ROLB commands make it possible for the program to remove the effects of its inaccurate processing.

You can use both ROLL and ROLB in batch programs. You can only use the ROLB command in batch programs if the system log is stored on direct access storage and if you have specified BKO=Y in the parm field of your JCL.

Issuing either of these commands causes DL/I to back out any changes your program has made to the database since its last checkpoint, or since the beginning of the program if your program has not issued a checkpoint.