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To: cluster <skrald@amossen.dk>
cc: pgsql-performance@postgresql.org
Subject: Re: FK triggers misused? 
In-reply-to: <evqm6g$29b1$1@news.hub.org> 
References: <evqm6g$29b1$1@news.hub.org>
Comments: In-reply-to cluster <skrald@amossen.dk>
	message dated "Sat, 14 Apr 2007 15:51:37 +0200"
Date: Sun, 15 Apr 2007 01:29:01 -0400
Message-ID: <26399.1176614941@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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cluster <skrald@amossen.dk> writes:
> It seems that the FK triggers for the table are evaluated even though
> none of the FK columns are altered.

Hm, they're not supposed to be, at least not in reasonably modern
PG releases (and one that breaks out trigger runtime in EXPLAIN ANALYZE
should be modern enough IIRC).  Exactly which PG release are you
running?  Can you provide a self-contained test case?

			regards, tom lane