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Date: Mon, 7 Jul 2003 15:47:06 -0700 (PDT)
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
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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.