The purging of task history is controlled using:
The default value for the retain task history flag is Y.
When the Retain Task History flag is set to N, task history will be purged during the next REORG job.
When the flag is set to N, you will be able to purge up to today's data or change to an earlier date when the reorg job is submitted. If the date is set to zeroes, the history is not purged. Similarly, if the flag is set to Y the history is not purged.
For information on the LANSA Reorg job, refer to 5.6.4 Submit Job to Reorganize the Database.