Re: Why are queries with subselects so slow?

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От Martijn van Oosterhout
Тема Re: Why are queries with subselects so slow?
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Msg-id 20030307062307.GH22303@svana.org
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Ответ на Why are queries with subselects so slow?  ("Robert Wille" <robertw@willeweb.com>)
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On Thu, Mar 06, 2003 at 10:38:09PM -0700, Robert Wille wrote:
> I am trying to execute an update that has a subselect, and it takes an extraordinarily long time.
> By performing the subselect in my application, and issuing the update multiple times, it appears that I can do the
entireupdate about 400 times faster. 

Try using EXISTS rather than IN. It tends to work better.

Hope this helps,
--
Martijn van Oosterhout   <kleptog@svana.org>   http://svana.org/kleptog/
> Support bacteria! They're the only culture some people have.

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