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Date: Mon, 7 Jul 2003 16:55:53 -0600 (MDT)
From: "scott.marlowe" <scott.marlowe@ihs.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:

> Hi,
> 
> 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?

Might a functional or partial index work here?