Using IN with subselect - Mailing list pgsql-general

From Dave Smith
Subject Using IN with subselect
Date
Msg-id 1101401346.7960.36.camel@playpen.candata.com
Whole thread Raw
Responses Re: Using IN with subselect
List pgsql-general
I have a query with an in subquery like

where x in (select x from y);

Now the subquery is not related to the outer query so it always returns
the same set. Is this subselect executed each time or just once? If it
is executed each time, if I create a function would that then be only
executed once?

--
Dave Smith
CANdata Systems Ltd
416-493-9020


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