A. Kretschmer wrote:
am  Thu, dem 28.06.2007, um 15:03:32 +1000 mailte Chris folgendes:
Hi all,

I'm trying to do an update of a reasonably large table and it's taking way too long so I'm trying to work out why and if I need to tweak any settings to speed it up.

The table is around 3.5 million records.

The query is

update table set domainname=substring(emailaddress from position('@' in emailaddress));

I think, this is a bad idea.
Because, first, you have 2 columns with nearly identical data
(mailaddres includes the domain and a extra domain field)

Yeh I know. I might have to go back to the drawing board on this one. The app has to work in mysql & postgres so I'm a bit limited in some of my approaches.

--
Postgresql & php tutorials
http://www.designmagick.com/

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