Re: Equivalent praxis to CLUSTERED INDEX?

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От Bruce Momjian
Тема Re: Equivalent praxis to CLUSTERED INDEX?
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Msg-id 200408280354.i7S3slb21543@candle.pha.pa.us
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Ответ на Re: Equivalent praxis to CLUSTERED INDEX?  (Gaetano Mendola <mendola@bigfoot.com>)
Ответы Re: Equivalent praxis to CLUSTERED INDEX?  (Greg Stark <gsstark@mit.edu>)
Список pgsql-performance
Gaetano Mendola wrote:
> | Right.  My point was that non-full fill is valuable for us only when
> | doing clustering, while for Oracle it is a win even in non-cluster cases
> | because of the way they update in place.
>
> Don't you think this will permit also to avoid extra disk seek and cache
> invalidation? If you are updating the row (0,1) I think is less expensive
> put the new version in (0,2) instead of thousand line far from that point.

It would, but does that outweigh the decreased I/O by having things more
densely packed?  I would think not.

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