Re: triggers within commit cycles

["R. Bruce Hoffman, Jr." <rbruceh@xxxxxxxxxxxxx>]

-----Original Message-----
From: Buck Calabro <Buck.Calabro@commsoft.net>
To: midrange-l@midrange.com <midrange-l@midrange.com>
Date: Monday, August 20, 2001 12:38 PM
Subject: RE: triggers within commit cycles


>>If I update a record in a file that has an update
>>trigger, then rollback the transaction using
>>commitment control, does the trigger program
>>fire again with the correct update that puts the
>>record back like it was?
>
>Based on Bruce's answers, I need to do some testing!  I'm not sure when the
>trigger fires; at HLL "UPDATE" time or at COMMIT time.  Either way, I
>thought that a ROLLBACK would fire the "opposite" trigger; i.e. if the
>record was added, the delete trigger would fire.  I MUST do some testing!


When the trigger fires is not the question. Why would a rollback fire an
"opposite" trigger and where does THAT trigger come from? What is the
opposite of an update trigger?

If you are doing IO in the trigger, you must decide whether or not to
include the IO in the commitment cycle or separate from that commit cycle.
If you separate it, the IO will be there after the rollback operation. It's
no different than calling a program.

Rollback operations, while they are IO in nature are different than standard
IO operations.

Would you want a delete cascade to happen just because you chose not to
insert a record into the database?

===========================================================
R. Bruce Hoffman, Jr.
 -- IBM Certified Specialist - AS/400 Administrator
 -- IBM Certified Specialist - RPG IV Developer

"America is the land that fought for freedom and then
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