Re: [PERFORM] update query taking too long

1. 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.

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