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From: "Fernando Hevia" <fhevia@ip-tel.com.ar>
To: "'Michael Glaesemann'" <grzm@seespotcode.net>,
	"'Mike Diehl'" <jdiehl@sandia.gov>
Cc: "'SQL Postgresql List'" <pgsql-sql@postgresql.org>
Subject: Re: Problem with phone list.
Date: Thu, 16 Aug 2007 10:56:17 -0300
Organization: IP-TEL
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--- Michael Glaesemann wrote:

> SELECT DISTINCT ON (phone_number)
>      phone_number, call_duration, id
> FROM calls
> ORDER BY phone_number
>      , call_duration DESC;

Wasn't acquainted with "DISTINCT ON (column)". 
I found it to be many times faster than other suggestions using JOIN.

Cheers,
Fernando.