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Date: Mon, 05 Nov 2007 18:49:26 +1300
From: Mark Kirkwood <markir@paradise.net.nz>
Subject: Re: partitioned table and ORDER BY indexed_field DESC LIMIT 1
In-reply-to: <87zly1as4y.fsf@oxford.xeocode.com>
To: Gregory Stark <stark@enterprisedb.com>
Cc: Luke Lonergan <llonergan@greenplum.com>,
	Heikki Linnakangas <heikki@enterprisedb.com>, Anton <anton200@gmail.com>,
	pgsql-performance@postgresql.org
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Gregory Stark wrote:
> cdbpathlocus_pull_above_projection
>   
>
> In particular this is the function I was hoping to see. Anyways as Tom pointed
> out previously there's precedent in Postgres as well for subqueries so I'm
> sure I'll be able to do it.
>
> (But I'm still not entirely convinced putting the append member vars into the
> eclasses would be wrong btw...)
>
>   
I spent today looking at getting this patch into a self contained state. 
Working against HEAD I'm getting bogged down in the PathKeyItem to 
PathKey/EquivalenceClass/EquivalenceMember(s) change. So I figured I'd 
divide and conquer to some extent, and initially provide a patch:

- against 8.2.(5)
- self contained  (i.e no mystery functions)

The next step would be to update to to HEAD. That would hopefully 
provide some useful material for others working on this.

Thoughts suggestions?

regards

Mark