Re: Performace comparison of indexes over timestamp fields

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От Alexander Staubo
Тема Re: Performace comparison of indexes over timestamp fields
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Msg-id 88daf38c0705220600y7ec63ed7x7920576abf92ea32@mail.gmail.com
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Ответ на Re: Performace comparison of indexes over timestamp fields  ("Steinar H. Gunderson" <sgunderson@bigfoot.com>)
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On 5/22/07, Steinar H. Gunderson <sgunderson@bigfoot.com> wrote:
> 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're right, and I'm wrong -- my head is not in the right place
today. B-trees are inefficient for intervals, but quite satisfactory
for range searches.

Alexander.

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