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ravikumar_sri2001 · Posted: Tue Oct 23, 2007 11:03 am Post subject: MQ - Roll back

Hi experts,

I have a MQ defined with trigger type "FIRST". A message is put in that MQ by a job and job ends. The queue trigegrs an application program, which is designed to process only one message. If the application program abends with ASRA, the retrieved message from the queue will be roll back. But, will the application program triggered again, since the queue depth is ONE ?.

Thanks,
Ravikumar.

bob_buxton · Posted: Wed Oct 24, 2007 4:02 am Post subject:

The application will be triggered again if the abending application is the only application that has the queue open for input.

See the MQ Application Programming Guide chapter on triggering for a full explanation of the trigger rules.

In your application you should check the backout count field in the message and discard messages when the count is greater than the backout threshold for the queue. This is to prevent an infinite trigger loop developing when there is something wrong with the message content that is causing the message to be repeatedly backed out.
_________________
Bob Buxton
Ex Websphere MQ for zOS development

ravikumar_sri2001 · Posted: Thu Oct 25, 2007 8:07 am Post subject:

Thank you very much Bob for your explanation. I will also go thru "MQ Application Programming Guide ".

Thanks,
Ravikumar.