Re: Postgres not willing to use an index?

Поиск
Список
Период
Сортировка
От Kevin Grittner
Тема Re: Postgres not willing to use an index?
Дата
Msg-id 498C21D8.EE98.0025.0@wicourts.gov
обсуждение исходный текст
Ответ на Re: Postgres not willing to use an index?  (Robert Haas <robertmhaas@gmail.com>)
Ответы Re: Postgres not willing to use an index?
Список pgsql-performance
>>> Robert Haas <robertmhaas@gmail.com> wrote:
> What's weird about this example is that when he sets enable_seqscan
to
> off, the bitmap index scan plan is actually substantially faster,
even
> though it in fact does scan nearly the entire heap.  I don't
> understand how it can be faster to scan the index and the heap than
to
> just scan the heap.

It's cached in the second test, maybe?

-Kevin

В списке pgsql-performance по дате отправления:

Предыдущее
От: Scott Marlowe
Дата:
Сообщение: Re: suggestions for postgresql setup on Dell 2950 , PERC6i controller
Следующее
От: Arjen van der Meijden
Дата:
Сообщение: Re: suggestions for postgresql setup on Dell 2950 , PERC6i controller