From: Tom Lane <tgl@sss.pgh.pa.us>
To: gurkan@resolution.com
Cc: pgsql-performance@postgresql.org
Subject: Re: how to optimize postgres 8.1
Date: Fri, 29 Sep 2006 14:07:32 -0400
Message-ID: <18273.1159553252@sss.pgh.pa.us> (raw)
In-Reply-To: <1159549965.451d540d3a997@www.resolution.com>
References: <1159549965.451d540d3a997@www.resolution.com>
gurkan@resolution.com writes:
> I need to increase performance on postgres,
Well, for starters, have you ANALYZEd your tables? That EXPLAIN output
looks suspiciously like default estimates. Then post EXPLAIN ANALYZE
(not just EXPLAIN) results for your problem query.
> If I run the query below with informix, it gives cost=107.
> with postgres with additional indexes it gives cost=407,
That comparison is meaningless --- I know of no reason to think that
informix measures cost estimates on the same scale we do. It'd be
interesting to see what query plan they use, though.
regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, gurkan@resolution.com
Subject: Re: how to optimize postgres 8.1
In-Reply-To: <18273.1159553252@sss.pgh.pa.us>
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