Re: constraint exclusion analysis caching

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От Gregory Stark
Тема Re: constraint exclusion analysis caching
Дата
Msg-id 87d4nvef8t.fsf@oxford.xeocode.com
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Ответ на constraint exclusion analysis caching  (Andrew Dunstan <andrew@dunslane.net>)
Ответы Re: constraint exclusion analysis caching  (Stephen Frost <sfrost@snowman.net>)
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"Andrew Dunstan" <andrew@dunslane.net> writes:

> Actual execution of the query in question was talking one tenth of that
> time.
>...
> but in principle it seems silly to keep paying the same penalty over and
> over again.

I would think constraint_exclusion only really makes sense if you're spending
a lot more time executing than planning queries. Either that means you're
preparing queries once and then executing them many many times or you're
planning much slower queries where planning time is insignificant compared to
the time to execute them.

--  Gregory Stark EnterpriseDB          http://www.enterprisedb.com Get trained by Bruce Momjian - ask me about
EnterpriseDB'sPostgreSQL training!
 


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