From: Carlo Stonebanks <stonec.register@sympatico.ca>
To: pgsql-performance@postgresql.org
Subject: Does FILTER in SEQSCAN short-circuit AND?
Date: Tue, 18 May 2010 18:28:25 -0400
Message-ID: <hsv49v$312j$1@news.hub.org> (raw)
Sample code:
SELECT *
FROM MyTable
WHERE foo = 'bar' AND MySlowFunc('foo') = 'bar'
Let's say this required a SEQSCAN because there were no indexes to support
column foo. For every row where foo <> 'bar' would the filter on the SEQSCAN
short-circuit the AND return false right away, or would it still execute
MySlowFunc('foo') ?
Thanks!
Carlo
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To: pgsql-performance@postgresql.org
Cc: stonec.register@sympatico.ca
Subject: Re: Does FILTER in SEQSCAN short-circuit AND?
In-Reply-To: <hsv49v$312j$1@news.hub.org>
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