From: David G Johnston <david.g.johnston@gmail.com>
To: pgsql-performance@postgresql.org
Subject: Re: Optimize query for listing un-read messages
Date: Thu, 1 May 2014 14:19:55 -0700 (PDT)
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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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To: pgsql-performance@postgresql.org
Cc: david.g.johnston@gmail.com
Subject: Re: Optimize query for listing un-read messages
In-Reply-To: <1398979195531-5802157.post@n5.nabble.com>
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