Re: No index only scan on md5 index

От: Albe Laurenz
Тема: Re: No index only scan on md5 index
Дата: ,
Msg-id: A737B7A37273E048B164557ADEF4A58B50FEB3D6@ntex2010i.host.magwien.gv.at
(см: обсуждение, исходный текст)
Ответ на: Re: No index only scan on md5 index  (Adam Brusselback)
Список: pgsql-performance

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No index only scan on md5 index  (Adam Brusselback, )
 Re: No index only scan on md5 index  ("David G. Johnston", )
  Re: No index only scan on md5 index  (Adam Brusselback, )
 Re: No index only scan on md5 index  (Tom Lane, )
  Re: No index only scan on md5 index  (Adam Brusselback, )
   Re: No index only scan on md5 index  (Albe Laurenz, )

Adam Brusselback wrote:
> I appreciate the response Tom, and you are correct that the workaround would not work in my case.
> 
> So no index expressions can return the their value without recomputing without that work around?  I
> learn something new every day it seems.
> Thank you for the alternate method.

No, what Tom said is that the check whether an "index only scan" was feasible
or not does not consider expressions.

Yours,
Laurenz Albe


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