Message-ID: <4C65B64E.9070005@agliodbs.com>
Date: Fri, 13 Aug 2010 14:17:02 -0700
From: Josh Berkus <josh@agliodbs.com>
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To: Greg Spiegelberg <gspiegelberg@gmail.com>
CC: pgsql-performance@postgresql.org
Subject: Re: Can WINDOW be used?
References: <AANLkTim5vdL6Q_Y3odgPEQAmBYrOVa=gDKzmNLko2abU@mail.gmail.com>
In-Reply-To: <AANLkTim5vdL6Q_Y3odgPEQAmBYrOVa=gDKzmNLko2abU@mail.gmail.com>
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> wxd0812=# EXPLAIN ANALYZE
> wxd0812-# SELECT * FROM
> wxd0812-#  (SELECT DISTINCT ON (key1_id,key2_id) * FROM sid120.data
> ORDER BY key1_id,key2_id,time_id DESC) x
> wxd0812-#  WHERE NOT deleted;

SELECT * FROM (
     SELECT data.*,
       rank() as rank over
            ( partition by key1_id, key2_id order by time_id DESC )
     FROM data
) as rankings
WHERE rank = 1 AND NOT deleted;


-- 
                                  -- Josh Berkus
                                     PostgreSQL Experts Inc.
                                     http://www.pgexperts.com