From: Stephan Szabo <sszabo@megazone23.bigpanda.com>
To: Markus Bertheau <twanger@bluetwanger.de>
Cc: pgsql-sql@postgresql.org
Subject: Re: avoid select expens_expr(col) like unneccessary calculations
Date: Mon, 7 Jul 2003 15:47:06 -0700 (PDT)
Message-ID: <20030707154329.J82767-100000@megazone23.bigpanda.com> (raw)
In-Reply-To: <1057617306.2617.6.camel@saphir>
On 8 Jul 2003, Markus Bertheau wrote:
> when you have
> select expensive_expression(column), * from table offset 20 limit 40
>
> can you somehow save the cost for the first 20 calculations of
> expensive_expression?
Right now the only way I can think of that might work is to push the
offset/limit into a subselect on table and then do the
expensive_expression at the top level.
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To: pgsql-sql@postgresql.org
Cc: sszabo@megazone23.bigpanda.com, twanger@bluetwanger.de
Subject: Re: avoid select expens_expr(col) like unneccessary calculations
In-Reply-To: <20030707154329.J82767-100000@megazone23.bigpanda.com>
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