Date: Mon, 30 Aug 2010 09:22:30 +0200
From: Andreas Kretschmer <akretschmer@spamfence.net>
To: pgsql-performance@postgresql.org
Subject: Re: Major performance problem after upgrade from 8.3 to
	8.4
Message-ID: <20100830072230.GA28373@tux>
References: <alpine.LFD.2.01.1008300802300.4121@bbs.intern>
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Gerhard Wiesinger <lists@wiesinger.com> wrote:

> I know that the data model is key/value pairs but it worked well in 8.3. 
> I need this flexibility.
>
> Any ideas?

If i understand the query correctly it's a pivot-table, right?

If yes, and if i where you, i would try to rewrite this query, to
something like:

select
  timestamp,
  sum (case when keyid = 1 then value else 0 end) as Raumsolltemperatur,
  ...
from
  log
group by
  timestamp;


Assuming you can read a german text:
http://www.pg-forum.de/h-ufig-gestellte-fragen-faq/4067-faq-zeilen-zu-spalten.html


Andreas
-- 
Really, I'm not out to destroy Microsoft. That will just be a completely
unintentional side effect.                              (Linus Torvalds)
"If I was god, I would recompile penguin with --enable-fly."   (unknown)
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