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Date: Mon, 15 Jan 2007 07:38:09 -0300
From: Alvaro Herrera <alvherre@commandprompt.com>
To: Luke Lonergan <LLonergan@greenplum.com>
Cc: Adam Rich <adam.r@sbcglobal.net>,
 "Joshua D. Drake" <jd@commandprompt.com>,
	Tom Lane <tgl@sss.pgh.pa.us>, "Craig A. James" <cjames@modgraph-usa.com>,
	PostgreSQL Performance <pgsql-performance@postgresql.org>
Subject: Re: max() versus order/limit (WAS: High update
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Luke Lonergan wrote:
> Adam,
> 
> This optimization would require teaching the planner to use an index for
> MAX/MIN when available.  It seems like an OK thing to do to me.

This optimization already exists, albeit for queries that use a single
table.

-- 
Alvaro Herrera                                http://www.CommandPrompt.com/
PostgreSQL Replication, Consulting, Custom Development, 24x7 support