Re: quick question: index optimisations on small tables

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От Peter Eisentraut
Тема Re: quick question: index optimisations on small tables
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Msg-id Pine.LNX.4.30.0108301931420.679-100000@peter.localdomain
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Ответ на quick question: index optimisations on small tables  ("Andrew Snow" <andrew@modulus.org>)
Список pgsql-general
Andrew Snow writes:

> Since it can get the answer straight out of the index, and if there are
> potentially numerous rows, looking up a b-tree is faster than a linear
> search?

You can't get the "answer straight out of the index".  You always need to
check back in the real table to see whether the row is visible to your
transaction.

--
Peter Eisentraut   peter_e@gmx.net   http://funkturm.homeip.net/~peter


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