Date: Mon, 26 Jun 2006 06:43:12 -0400
From: Andrew Sullivan <ajs@crankycanuck.ca>
To: pgsql-sql@postgresql.org
Subject: Re: Fwd: Start up question about triggers
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On Fri, Jun 23, 2006 at 10:29:33PM -0500, Aaron Bono wrote:
> 
> What I really cannot find is a way to _dynamically_ in the trigger ask what
> COLUMNS are in OLD and NEW.  If we had:

All of the columns, of course.  When the tuple is UPDATEd, even if
you did not mention some columns in your UPDATE, there is an OLD
value and a NEW value.  They're the same.

> I wish I had more experience with stored procedures - I know what I would
> try to do, just not if it is possible or how to implement it.

I think what Tom (but I don't want to put words in his mouth) and,
certainly, I have been saying is that your plan to get the list of
transform commands is fundamentally misguided.  If you want to track
changes, then that's what you should do: track what changed.

Note that there is a project that already, in fact, does this for you
as part of how it works: Slony-I.

A

-- 
Andrew Sullivan  | ajs@crankycanuck.ca
When my information changes, I alter my conclusions.  What do you do sir?
		--attr. John Maynard Keynes