Re: immutable functions vs. join for lookups ?

От: Enrico Weigelt
Тема: Re: immutable functions vs. join for lookups ?
Дата: ,
Msg-id: 20050421192357.GC16548@nibiru.borg.metux.de
(см: обсуждение, исходный текст)
Ответ на: Re: immutable functions vs. join for lookups ?  (Tom Lane)
Ответы: Re: immutable functions vs. join for lookups ?  (Dawid Kuroczko)
Список: pgsql-performance

Скрыть дерево обсуждения

immutable functions vs. join for lookups ?  (Enrico Weigelt, )
 Re: immutable functions vs. join for lookups ?  (Tom Lane, )
  Re: immutable functions vs. join for lookups ?  (Enrico Weigelt, )
   Re: immutable functions vs. join for lookups ?  (Jaime Casanova, )
    Re: immutable functions vs. join for lookups ?  (Enrico Weigelt, )
     Re: immutable functions vs. join for lookups ?  (Dawid Kuroczko, )
 Re: immutable functions vs. join for lookups ?  (Dawid Kuroczko, )
 Re: immutable functions vs. join for lookups ?  ("Merlin Moncure", )
  Re: immutable functions vs. join for lookups ?  (Dawid Kuroczko, )
   Re: immutable functions vs. join for lookups ?  ("Jim C. Nasby", )
    Re: immutable functions vs. join for lookups ?  (Dawid Kuroczko, )
     Re: immutable functions vs. join for lookups ?  (Christopher Kings-Lynne, )
     Re: immutable functions vs. join for lookups ?  (Christopher Kings-Lynne, )
  Re: immutable functions vs. join for lookups ?  (Tom Lane, )
   Re: immutable functions vs. join for lookups ?  (Greg Stark, )
    Re: immutable functions vs. join for lookups ?  (Tom Lane, )
     Re: immutable functions vs. join for lookups ?  (Enrico Weigelt, )
      Re: immutable functions vs. join for lookups ?  (Dawid Kuroczko, )

* Tom Lane <> wrote:

<snip>
> Yeah, I was actually thinking about a two-step process: inline the
> function to produce somethig equivalent to a handwritten scalar
> sub-SELECT, and then try to convert sub-SELECTs into joins.

... back to my original question ...

What kind of query should I use ?
Is a join better than a function ?


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