Re: Optimize query for listing un-read messages

From: David G Johnston <david(dot)g(dot)johnston(at)gmail(dot)com>
To: pgsql-performance(at)postgresql(dot)org
Subject: Re: Optimize query for listing un-read messages
Date: 2014-05-01 21:19:55
Message-ID: 1398979195531-5802157.post@n5.nabble.com
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How does something like:

WITH unreads AS (
SELECT messageid FROM message
EXCEPT
SELECT messageid FROM message_property WHERE personid=1 AND has_read
)
SELECT ...
FROM unreads
JOIN messages USING (messageid)
;

perform?

David J.

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