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Date: Thu, 10 Jun 2010 21:22:11 +0200
From: Jochen Erwied <jochen@pgsql-performance.erwied.eu>
Organization: Creative Chaos Computing
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To: Anne Rosset <arosset@collab.net>
CC: pgsql-performance@postgresql.org
Subject: Re: Need to increase performance of a query
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Thursday, June 10, 2010, 8:36:08 PM you wrote:

> psrdb=3D# (SELECT
> psrdb(#        MAX(item_rank.rank) AS maxRank
> psrdb(# FROM
> psrdb(#        item_rank item_rank
> psrdb(# WHERE
> psrdb(#        item_rank.project_id=3D'proj2783'
> psrdb(#         AND item_rank.pf_id IS NULL
> psrdb(#
> psrdb(# )
> psrdb-# ORDER BY
> psrdb-# maxRank DESC;

Don't think it does really matter, but why do you sort a resultset=20
consisting of only one row?

--=20
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