Re: Why so much time difference with a same query/plan?

От: Bruno Wolff III
Тема: Re: Why so much time difference with a same query/plan?
Дата: ,
Msg-id: 20041231061042.GA17555@wolff.to
(см: обсуждение, исходный текст)
Ответ на: Re: Why so much time difference with a same query/plan?  (Karl Vogel)
Список: pgsql-performance

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Why so much time difference with a same query/plan?  (Litao Wu, )
 Re: Why so much time difference with a same query/plan?  (Litao Wu, )
  Re: Why so much time difference with a same query/plan?  (Yann Michel, )
   Re: Why so much time difference with a same query/plan?  (Karl Vogel, )
    Re: Why so much time difference with a same query/plan?  (Bruno Wolff III, )

On Sun, Dec 26, 2004 at 13:30:15 +0100,
  Karl Vogel <> wrote:
>
> This depends on the version of Oracle you're using. Oracle 9i
> introduced Index Skip Scans:
>
>  http://www.oracle.com/technology//products/oracle9i/daily/apr22.html
>
> I don't know whether pg has something similar?

Postgres doesn't currently do this. There was some discussion about this
not too long ago, but I don't think anyone indicated that they were going to
work on it for 8.1.

Postgres can use the leading part of a multikey index to start a scan,
but it will just do a normal index scan with a filter.


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