Re: faster SELECT

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: sferriol <sylvain(dot)ferriol(at)imag(dot)fr>
Cc: pgsql-general(at)postgresql(dot)org
Subject: Re: faster SELECT
Date: 2004-03-08 15:03:01
Message-ID: 3664.1078758181@sss.pgh.pa.us
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sferriol <sylvain(dot)ferriol(at)imag(dot)fr> writes:
> for example
> 1) select ... where a and b;
> 2) select ... where b and a;
> 1 and 2 will use the same cpu time or not ?

They'll generate the same query plan, except possibly for the evaluation
order of a and b (assuming that those end up attached to the same plan
node in the first place). What that means for CPU time would depend on
what a and b are.

What are you trying to accomplish, exactly? Your question is
essentially useless to ask or answer as it stands, so you'll
need to readjust your thinking.

regards, tom lane

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