Re: Equivalent praxis to CLUSTERED INDEX? - Mailing list pgsql-performance

From Bruce Momjian
Subject Re: Equivalent praxis to CLUSTERED INDEX?
Date
Msg-id 200408280354.i7S3slb21543@candle.pha.pa.us
Whole thread Raw
In response to Re: Equivalent praxis to CLUSTERED INDEX?  (Gaetano Mendola <mendola@bigfoot.com>)
Responses Re: Equivalent praxis to CLUSTERED INDEX?
List 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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