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From: Gaetano Mendola <mendola@gmail.com>
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Subject: Re: Inoptimal query plan for max() and multicolumn index
Date: Fri, 15 Jul 2011 09:14:45 +0200
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On 20/06/2011 07:35, Vladimir Kulev wrote:

> But this does not work:
> # explain analyze select max(timestamp) from sms where number in
> ('5502712','5802693','5801981');

Try to rewrite that query this way:

explain analyze select timestamp from sms where number in 
('5502712','5802693','5801981') order by timestamp desc limit 1;


Regards
Gaetano Mendola