I just read the lead ups to this post - didn't see Tom and Greg's comments.

The approach we took was to recognize the ordering of child nodes and propagate 
that to the append in the special case of only one child (after CE).  This is 
the most common use-case in 'partitioning', and so is an easy, high payoff low 
amount of code fix.

I'd suggest we take this approach while also considering a more powerful set of 
append merge capabilities.

- Luke

Msg is shrt cuz m on ma treo

 -----Original Message-----
From:   Luke Lonergan [mailto:[EMAIL PROTECTED]
Sent:   Saturday, October 27, 2007 03:14 PM Eastern Standard Time
To:     Heikki Linnakangas; Anton
Cc:     pgsql-performance@postgresql.org
Subject:        Re: [PERFORM] partitioned table and ORDER BY indexed_field DESC 
LIMIT 1

And I repeat - 'we fixed that and submitted a patch' - you can find it in the 
unapplied patches queue.

The patch isn't ready for application, but someone can quickly implement it I'd 
expect.

- Luke

Msg is shrt cuz m on ma treo

 -----Original Message-----
From:   Heikki Linnakangas [mailto:[EMAIL PROTECTED]
Sent:   Saturday, October 27, 2007 05:20 AM Eastern Standard Time
To:     Anton
Cc:     pgsql-performance@postgresql.org
Subject:        Re: [PERFORM] partitioned table and ORDER BY indexed_field DESC 
LIMIT 1

Anton wrote:
> I repost here my original question "Why it no uses indexes?" (on
> partitioned table and ORDER BY indexed_field DESC LIMIT 1), if you
> mean that you miss this discussion.

As I said back then:

The planner isn't smart enough to push the "ORDER BY ... LIMIT ..."
below the append node.

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

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