To: pgsql-performance@postgresql.org
From: "Holger Hoffstaette" <holger@wizards.de>
Subject: Re: ??: Postgresql update op is very very slow
Date: Thu, 26 Jun 2008 14:40:59 +0200
Organization: The Fists of the White Lotus
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Hi -

I have been following this thread and find some of the recommendations
really surprising. I understand that MVCC necessarily creates overhead,
in-place updates would not be safe against crashes etc. but have a hard
time believing that this is such a huge problem for RDBMS in 2008. How do
large databases treat mass updates? AFAIK both DB2 and Oracle use MVCC
(maybe a different kind?) as well, but I cannot believe that large updates
still pose such big problems.
Are there no options (algorithms) for adaptively choosing different
update strategies that do not incur the full MVCC overhead?

Holger

(Disclaimer: I'm not a professional DBA, just a curious developer).