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To: Matthew Wakeling <matthew@flymine.org>
cc: pgsql-performance@postgresql.org
Subject: Re: Slow index 
In-reply-to: <alpine.DEB.1.10.0809251301320.19066@aragorn.flymine.org> 
References: <alpine.DEB.1.10.0809251301320.19066@aragorn.flymine.org>
Comments: In-reply-to Matthew Wakeling <matthew@flymine.org>
	message dated "Thu, 25 Sep 2008 13:07:09 +0100"
Date: Thu, 25 Sep 2008 09:11:58 -0400
Message-ID: <5564.1222348318@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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Matthew Wakeling <matthew@flymine.org> writes:
> Hi all. I'm having an interesting time performance-wise with a set of indexes. 
> Any clues as to what is going on or tips to fix it would be appreciated.

Are the indexed columns all the same datatype?  (And which type is it?)

It might be helpful to REINDEX the "slow" index.  It's possible that
what you're seeing is the result of a chance imbalance in the btree,
which reindexing would fix.

			regards, tom lane