Re: avoiding seqscan?

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От Palle Girgensohn
Тема Re: avoiding seqscan?
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Msg-id 202370000.1064843102@durian.pingpong.net
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Ответ на avoiding seqscan?  (Palle Girgensohn <girgen@pingpong.net>)
Список pgsql-performance
--On måndag, september 29, 2003 15.32.31 +0200 Gaetano Mendola
<mendola@bigfoot.com> wrote:

> Are not absolutelly bad but sometimes that path that you choose is not
> the optimal, in postgres 7.4 use the explicit join will be less
> limitative for the planner.
>
> Regards
> Gaetano Mendola

Ah, OK. True! In this case though, the sql questions are crafted with great
care, since we have a lot of data in a few of the tables, other are almost
empty, so we try to limit the amount of data as early as possible. Our
experience says that we often do a better job than the planner, since we
know which tables are "fat". Hence, we have actually moved to exlicit joins
in questions and sometimes gained speed.

But, in the general case, implicit might be better, I guess.

Regards,
Palle




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