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To: Ben <bench@silentmedia.com>
cc: pgsql-performance@postgresql.org
Subject: Re: pg_trgm indexes giving bad estimations? 
In-reply-to: <Pine.LNX.4.64.0610312106260.5452@GRD.cube42.tai.silentmedia.com>
References: <FFBBFAF9-7BA8-42BE-8958-5F6702AB2663@silentmedia.com>
	<5872.1160013267@sss.pgh.pa.us>
	<Pine.LNX.4.64.0610312106260.5452@GRD.cube42.tai.silentmedia.com>
Comments: In-reply-to Ben <bench@silentmedia.com>
	message dated "Tue, 31 Oct 2006 21:41:38 -0800"
Date: Wed, 01 Nov 2006 01:01:17 -0500
Message-ID: <13752.1162360877@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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Ben <bench@silentmedia.com> writes:
> Unfortunately, it's not at all clear to me from reading 
> http://www.postgresql.org/docs/8.1/interactive/xoper-optimization.html#AEN33077
> how like impliments selectivity. Any pointers on where to look?

likesel() and subsidiary functions in src/backend/utils/adt/selfuncs.c

			regards, tom lane