Re: Triggers

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

----- Original Message -----
From: <MWalter@hanoverwire.com>
To: <midrange-l@midrange.com>
Sent: Thursday, May 23, 2002 1:46 PM
Subject: Triggers


> What are the advantages, if any, of *before *insert as compared to *after
> *Insert trigger programs? Or doesn't it really matter? I am using the
> trigger to write an audit record. There is no validation or business logic
> going on here. The only thing I can think of is that the database insert
> will complete if using a *after trigger if the trigger program were to
fail
> for some reason.

Before triggers let you change the data in the buffer going to the database
because it happens before the write.

After triggers fire after the record is put in the database and don't afford
you the opportunity to screw with the data before it hits the database.

As for trigger failures, the write should be told to fail and the commit
logic should be asked to roll back the transaction.

===========================================================
R. Bruce Hoffman, Jr.
 -- IBM Certified Specialist - iSeries Administrator
 -- IBM Certified Specialist - RPG IV Developer

"Suppose you were an idiot...
  And suppose you were a member of Congress...
  But I repeat myself."
    - Mark Twain