Re: Performace comparison of indexes over timestamp fields

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От Steinar H. Gunderson
Тема Re: Performace comparison of indexes over timestamp fields
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Msg-id 20070522124320.GA24779@uio.no
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Ответ на Re: Performace comparison of indexes over timestamp fields  ("Alexander Staubo" <alex@purefiction.net>)
Ответы Re: Performace comparison of indexes over timestamp fields
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On Tue, May 22, 2007 at 02:39:33PM +0200, Alexander Staubo wrote:
> PostgreSQL uses B-tree indexes for scalar values. For an expression
> such as "t between a and b", I believe it's going to match both sides
> of the table independently (ie., t >= a and t <= b) and intersect
> these subsets. This is inefficient.

A B-tree index can satisfy range queries such as this.

> You should get better performance by mapping timestamps to a
> one-dimensional plane and indexing them using GiST. GiST implements an
> R-tree-like structure that supports bounding-box searches.

You may be thinking of interval overlaps?

/* Steinar */
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