Re: left join on a view takes significantly more time.

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От Josh Berkus
Тема Re: left join on a view takes significantly more time.
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Msg-id 200403311549.29211.josh@agliodbs.com
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Ответ на left join on a view takes significantly more time.  (Manuel Sugawara <masm@fciencias.unam.mx>)
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Manuel,

> I'm facing a wired problem. When I left join two tables PostgreSQL is
> able to do it fast using the corresponding indices, However, if I
> define a simple view (to format the data) on one of the tables, the
> left join does not use the indices. Is something wrong here?

At a guess, the complex CASE statements are causing the planner to behave 
badly.   What happens if you do a straight join and not a left join?

Also, it's generally a good idea to put your join expression in the same order 
as the referenced tables.  You confused me and you could confuse the planner 
at some stage.

-- 
-Josh BerkusAglio Database SolutionsSan Francisco



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