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To: Ben <bench@silentmedia.com>
cc: Daniel Caune <daniel.caune@ubisoft.com>, pgsql-performance@postgresql.org
Subject: Re: index usage 
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 <Pine.LNX.4.64.0607281359030.11400@GRD.cube42.tai.silentmedia.com>
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	<Pine.LNX.4.64.0607281359030.11400@GRD.cube42.tai.silentmedia.com>
Comments: In-reply-to Ben <bench@silentmedia.com>
	message dated "Fri, 28 Jul 2006 13:59:57 -0700"
Date: Fri, 28 Jul 2006 17:06:55 -0400
Message-ID: <1236.1154120815@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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Ben <bench@silentmedia.com> writes:
> It's volatile, but it will always return an integer.

If it's volatile then it can't be used for an index condition.

			regards, tom lane