Date: Thu, 13 Oct 2005 10:11:43 -0400
From: Andrew Sullivan <ajs@crankycanuck.ca>
To: pgsql-sql@postgresql.org
Subject: Re: pg, mysql comparison with "group by" clause
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	<87oe5uyrfs.fsf@stark.xeocode.com>
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On Thu, Oct 13, 2005 at 12:24:55AM -0400, Greg Stark wrote:

> Well the "constants and the like" are precisely the point. There
> are plenty of cases where adding the column to the GROUP BY is
> unnecessary and since Postgres makes no attempt to prune them out,
> inefficient.

But inefficient pruning is an optimiser problem, not something that
should lead one to invent a whole syntax change that (a) violates the
standard and (b) is at least somewhat opaque in meaning.  The right
thing to do is surely to make the optimiser smarter, no?  (Think,
"What does DB2 have that we don't?")

A

-- 
Andrew Sullivan  | ajs@crankycanuck.ca
This work was visionary and imaginative, and goes to show that visionary
and imaginative work need not end up well. 
		--Dennis Ritchie