Re: Limit + group + join

From: Tobias Brox
Subject: Re: Limit + group + join
Date: ,
Msg-id: 20050828014240.GB5736@tobias.lan
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In response to: Re: Limit + group + join  (Mark Kirkwood)
List: pgsql-performance

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Limit + group + join  (Tobias Brox, )
 Re: Limit + group + join  ("Jeffrey W. Baker", )
  Re: Limit + group + join  (Tobias Brox, )
  Re: Limit + group + join  ("Jeffrey W. Baker", )
 Re: Limit + group + join  (Mark Kirkwood, )
  Re: Limit + group + join  (Tobias Brox, )
  Re: Limit + group + join  (Stephan Szabo, )
  Re: Limit + group + join  (Tom Lane, )
   Re: Limit + group + join  (Mark Kirkwood, )
    Re: Limit + group + join  (Tom Lane, )
   Re: Limit + group + join  (Mark Kirkwood, )
    Re: Limit + group + join  (Tom Lane, )
     Re: Limit + group + join  (Mark Kirkwood, )
      Re: Limit + group + join  (Tobias Brox, )
   Re: Limit + group + join  (Greg Stark, )
 Re: Limit + group + join  ("Merlin Moncure", )
 Re: Limit + group + join  ("Merlin Moncure", )

[Tom Lane]
> I looked into this and (...) I've committed some changes that hopefully will
> let 8.1 be smarter about GROUP BY ... LIMIT queries.

[Mark Kirkwood]
> Very nice :-)
(...)
> This is 8.1devel from today.

Splendid :-) Unfortunately we will not be upgrading for some monthes still,
but anyway I'm happy.  This provides yet another good argument for upgrading
sooner.  I'm also happy to see such a perfect match:

 - A problem that can be reduced from beeing complex and
   production-specific, to simple and easily reproducible.

 - Enthusiastic people testing it and pinpointing even more precisely what
   conditions will cause the condition

 - Programmers actually fixing the issue

 - Testers verifying that it was fixed

Long live postgresql! :-)

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From: Tobias Brox
Date:
Subject: Re: Limit + group + join
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