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Date: Sat, 24 Sep 2011 11:38:48 +0200
From: Andreas <maps.on@gmx.net>
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To: pgsql-sql@postgresql.org
Subject: Better way to check more than 1 value NOT IN (...)
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Hi,
I've got to check if 2 values are not in a set that is dynamically 
calculated by a function.

The query looks like

select  some_id, ....
from .....
where   10  is not in ( select x from my_function (some_id))
and   20  is not in ( select x from my_function (some_id))

Is there a efficiency issue with calculating the set twice ?
Can I somehow check both (or more) values at once?