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From: Poul Møller Hansen <freebsd@pbnet.dk>
To: pgsql-general@postgresql.org
Subject: Optimizing query
Date: Mon, 15 Aug 2005 10:38:26 +0200
Message-ID: <43005482.7020105@pbnet.dk> (raw)

I have a problem creating a usable index for the following simple query:
SELECT * FROM my.table WHERE node = '10' ORDER BY id DESC LIMIT 1

id is a serial, so the query is to find the latest entry to a given node 
and id is the primary key.
The table contains around 1 million records and the query takes around 2 
seconds.

I have tried to make an index on node and also on both id & node, but is 
doesn't lower the
query time.

What am I doing wrong ?

Thanks,
Poul

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