Horton

Re: Nested CASE-WHEN scoping

Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>

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From: Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>
To: Pavel Stehule <pavel.stehule@gmail.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2011-06-16T20:27:00Z
Lists: pgsql-hackers 
On 16.06.2011 22:46, Pavel Stehule wrote:
> I have a query - should be ExpressionParam used for removing a
> multiple function call when composite result is expanded?
>
> With some similar optimization a SELECT (fce(x)).* FROM tab will be optimal

Hmm, I don't think it will work as is for that purpose, as each 
targetlist item is a separate expression, and ExpressionParams only work 
within an expression.

-- 
   Heikki Linnakangas
   EnterpriseDB   http://www.enterprisedb.com