Re: Why do after row triggers exists?

From: FC <flavio_at_tin.it>
Date: Sat, 18 Jan 2003 11:06:26 GMT
Message-ID: <SyaW9.45714$0v.1411856@news1.tin.it>

"Jaap W. van Dijk" <j.w.vandijk.removethis_at_hetnet.nl> wrote in message news:8i5i2vk16ji6vvkggfbm4mbtrkv74hjop9_at_4ax.com...
> Hi,
>
> A general question:
>
> What can be accomplished with an after row trigger that can not be
> done with a before row trigger?
>
> Jaap.

If your "after trigger" code gets executed, it means that your record satisfies certain rules.
"Before" triggers allow you to amend the record and change its values altogether, but the record has still to be inserted/update/deleted and checked against the constraints.
"After" triggers occur after checking prerequisites, like referential integrity constraints or column constraints and after executing the trigger firing action.

You may want to read the Concepts book for version 8.1.7 at the following address:
http://tahiti.oracle.com/pls/tahiti/tahiti.show_toc?partno=a76965 where there is a specific section dedicated to triggers.

If you refer to a later version of Oracle, look for "Concepts" under the corresponding document library on the same site.

Bye,
Flavio Received on Sat Jan 18 2003 - 05:06:26 CST