Re: Does a 'stable' deferred trigger execution order exist? -> answer: yes

From: Frank van Vugt <ftm(dot)van(dot)vugt(at)foxi(dot)nl>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: pgsql-general(at)postgresql(dot)org
Subject: Re: Does a 'stable' deferred trigger execution order exist? -> answer: yes
Date: 2004-08-17 19:42:16
Message-ID: 200408172142.17025.ftm.van.vugt@foxi.nl
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> > Any execution order for regular triggers would be as good as any other
> This is perhaps true for "cleanly designed" applications, but people
> have requested that we nail down the execution order, and we have
> responded by specifying that it's alphabetical within an event.

I understand and actually meant to say that since nothing should 'depend' on
any particular order, executing these triggers alphabetically seems a logical
approach with the extra bonus you mention.

> The intention was certainly to apply this to AFTER as well
> as BEFORE triggers. We'll need to look and see why it's not working.

Just to avoid any misunderstandings:

- regular triggers DO execute in alphabetical order

- it's the deferred triggers that execute per event in order of definition

> > at least the sets itself are executed in the same order as the original
> > events they fired upon.
> Right. This is handled by appending new pending-trigger events to a
> global list when they are detected. Barring oddities such as different
> deferral specifications, they should be executed in order of detection.

That's the big 'YES' I was looking for ;-) Thanks.

> I would have expected triggers for the same event to be inserted in
> alphabetical order ...

Yep, me too, but apart from the fact that I'm o.k. with the way it currently
works, I imagine this is not exactly a high-priority issue right now ;-)

Thanks again for the replies.

--
Best,

Frank.

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