Re: Union strange explain

From: "Gaetano Mendola" <mendola(at)bigfoot(dot)com>
To: "Stephan Szabo" <sszabo(at)megazone23(dot)bigpanda(dot)com>
Cc: <pgsql-admin(at)postgresql(dot)org>
Subject: Re: Union strange explain
Date: 2002-07-05 10:17:16
Message-ID: 005001c2240d$23d176e0$070afea9@GMENDOLA2
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Stephan wrote:
> number of rows returned). I think there was some question about
> whether it was safe to do that optimization (ie,
> is select * from (a union [all] b) where condition
> always the same as
> select * from a where condition union [all]
> select * from b where condition
> )

Yes but with a View the condition is always extern.
I'm understanding that I don't have any possibility to
optimize that view, I'm wrong ?

Ciao
Gaetano

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