Re: Perfomance of views

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От Richard Huxton
Тема Re: Perfomance of views
Дата
Msg-id 4360F4F7.8070503@archonet.com
обсуждение исходный текст
Ответ на Re: Perfomance of views  (Jan Wieck <JanWieck@Yahoo.com>)
Список pgsql-performance
Jan Wieck wrote:
> On 10/27/2005 7:29 AM, Richard Huxton wrote:
>> Svenne Krap wrote:
>>
>>> What do you mean exactly but "pushing conditions inside" ?
>>
>> If I have something like "SELECT * FROM complicated_view WHERE foo =
>> 7" then the planner can look "inside" complicated_view and see where
>> it can attach the condition "foo=7", rather than running the query and
>> applying the condition at the end.
>
> Sorry, but the planner doesn't attach the condition anywhere. It is the
> rewriter that takes the actual query, replaces the views rangetable and
> expression entries with the actual underlying objects and adds the views
> condition with an AND to the queries condition. Simply example:

Thanks for the correction Jan.

--
   Richard Huxton
   Archonet Ltd

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