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From: Josh Berkus <josh@agliodbs.com>
Reply-To: josh@agliodbs.com
Organization: Aglio Database Solutions
To: Marco Muratori <marco.muratori@emaze.net>,
	<pgsql-sql@postgresql.org>
Subject: Re: query problem
Date: Thu, 29 Aug 2002 13:45:25 -0700
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Marco,

> Is there a way to obtain this records by performing one
> single query and not by making for each city something like
> "SELECT city,date FROM table WHERE city=3D'London' AND date>'2002-07-19
> 15:39:15+00' ORDER BY date ASC LIMIT 1;"?

Close.  Try:

SELECT city, MAX("date") as last_date
FROM table
WHERE "date" > $date
GROUP BY city
ORDER BY city

Though as an aggregate query, this will be slow on large tables.

--=20
-Josh Berkus
 Aglio Database Solutions
 San Francisco