I have done this, but you do not want the trigger changing the library list if at all possible, it will cause performance issues with the database. If you need multiple processing programs, you can key the data queue, and have multiple programs taking messages off the data queue each looking for a specific key. Or best way is you can make sure that the job processing the data queue has all the necessary libraries to process anything it could possibly get.
It is important that a processing program exist, otherwise the data queue will overflow and become very slow, on read and on write. This can be taken care of procedurally. Even if you have a monitoring program, what makes sure the monitoring program is running? And what makes sure the program that monitors the monitoring program is running, and so on, and so on. At some point you get down to a person making sure something is running. Once we got our processes in place, and the appropriate start ups working there was no issue with DQ the processing program going down. That's just the nature of the I.
Mark Murphy
STAR BASE Consulting, Inc.
mmurphy@xxxxxxxxxxxxxxx
-----midrange-l-bounces@xxxxxxxxxxxx wrote: -----
To: Midrange Systems Technical Discussion <midrange-l@xxxxxxxxxxxx>
From: Jeff Young
Sent by: midrange-l-bounces@xxxxxxxxxxxx
Date: 06/17/2011 12:34PM
Subject: Re: Trigger Processing Question
Paul,
I still need to know if the program that receives the data queue entry is
active.
This will be a program running in a NOMAX jobs subsystem, but needs to be
library list sensitive.
My current logic is to call a program with the data needed for the data queue
and test if the processing job for the environment is active.
I do this using the List Active Jobs API and if the job is not active, I submit
it.
My question is what is the best way to call this program from the trigger to
ensure that I will always get the current version?
Thanks,,
Jeff Young
Sr. Programmer Analyst
________________________________
From: "Morgan, Paul" <Paul.Morgan@xxxxxxxxxxx>
To: Midrange Systems Technical Discussion <midrange-l@xxxxxxxxxxxx>
Sent: Fri, June 17, 2011 11:49:05 AM
Subject: RE: Trigger Processing Question
Jeff,
Why must the trigger program check if the processing program is active? That
shouldn't be done in the process that fires the trigger. Do that with some sort
of scheduled job to occasionally check if the process monitoring the data queue
is active.
Why must the trigger determine if the data queue exists? I'd just have the
trigger program push an entry into the data queue. Monitor or trap that push
into the data queue for an error. If you trap a 'data queue doesn't exist' error
then do something about it.
Paul Morgan
Principal Programmer Analyst
IT Supply Chain/Replenishment
-----Original Message-----
From: midrange-l-bounces@xxxxxxxxxxxx [mailto:midrange-l-bounces@xxxxxxxxxxxx]
On Behalf Of Jeff Young
Sent: Friday, June 17, 2011 11:34 AM
To: Midrange Systems Technical Discussion
Subject: Re: Trigger Processing Question
Hi Paul,
That is basicaly what I am doing, but I need to determine if the data queue
exists and if the processing program is active.
I have a program that will do that, but what is the best way for the trigger to
call it so that if needed I can make adjustments to it without having to
worry about what version the trigger is actually calling.
Thanks,
Jeff Young
Sr. Programmer Analyst
________________________________
From: "Morgan, Paul" <Paul.Morgan@xxxxxxxxxxx>
To: Midrange Systems Technical Discussion <midrange-l@xxxxxxxxxxxx>
Sent: Fri, June 17, 2011 10:43:08 AM
Subject: RE: Trigger Processing Question
Jeff,
Fire off an entry into a data queue from the trigger program. Have another
process already running which is monitoring the queue and processes the entry to
call the other program to do some other processing. It's possible for you to
shut down the process and restart it to make changes to the other program. As
long as the data queue is available the trigger program can continue to fire
entries into the queue.
I wouldn't do any checking for a data queue or process in the trigger program.
Neither would I submit a job or call the program from the trigger program. You
want to reduce as much as possible any possibility of an error or delay with the
trigger program.
If you want to make changes to the trigger program you should use the Trigger
Mediator pattern.
Paul Morgan
Principal Programmer Analyst
IT Supply Chain/Replenishment
-----Original Message-----
From: midrange-l-bounces@xxxxxxxxxxxx [mailto:midrange-l-bounces@xxxxxxxxxxxx]
On Behalf Of Jeff Young
Sent: Friday, June 17, 2011 10:27 AM
To: midrange-l@xxxxxxxxxxxx
Subject: Trigger Processing Question
V6R1
I have a trigger program that is going to be called thousands of times during
the day.
This program will test some fields in the old and new record and then fire off a
program to do some other processing if they are changed.
At this time this is the only trigger being used, so the Trigger Mediator
program is overkill.
I want to be able to make changes to the program doing the proessing if needed.
I will initialy call a program to test if a data queue exits and if the
processing job is already active and waiting for a message.
If not, the program will create the data queue and then submit the processing.
What is the best method to call this program?
Dynamic call from the Trigger?
Submit job to batch ?
Some other method?
All suggestions will be appreciated.
Thanks,
Jeff Young
Sr. Programmer Analyst
midrange.com
