Re: Stable function being evaluated more than once in a single query

От: Tom Lane
Тема: Re: Stable function being evaluated more than once in a single query
Дата: ,
Msg-id: 935.1137040403@sss.pgh.pa.us
(см: обсуждение, исходный текст)
Ответ на: Stable function being evaluated more than once in a single query  (Mark Liberman)
Ответы: Re: Stable function being evaluated more than once in a single query  ("Jim C. Nasby")
Список: pgsql-performance


Mark Liberman <> writes:
> I've got a set-returning function,  defined as STABLE, that I reference twice
> within a single query, yet appears to be evaluated via two seperate function
> scans.

There is no guarantee, express or implied, that this won't be the case.

(Seems like we just discussed this a couple days ago...)

            regards, tom lane


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