Re: performance with query

От: Kevin Grittner
Тема: Re: performance with query
Дата: ,
Msg-id: 4A3774C40200002500027BED@gw.wicourts.gov
(см: обсуждение, исходный текст)
Ответ на: Re: performance with query  (Alberto Dalmaso)
Список: pgsql-performance

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performance with query  (Alberto Dalmaso, )
 Re: performance with query  (Joshua Tolley, )
 Re: performance with query  ("Kevin Grittner", )
 Re: performance with query  (Alberto Dalmaso, )
  Re: performance with query  (Matthew Wakeling, )
   Re: performance with query  (Alberto Dalmaso, )
    Re: performance with query  (Tom Lane, )
     Re: performance with query  (Alberto Dalmaso, )
      Re: performance with query  (Tom Lane, )
      Re: performance with query (OT)  ("Albe Laurenz", )
    Re: performance with query  ("Kevin Grittner", )
  Re: performance with query  ("Kevin Grittner", )
   Re: performance with query  (Alberto Dalmaso, )
    Re: performance with query  ("Kevin Grittner", )
    Re: performance with query  ("Kevin Grittner", )
     Re: performance with query  (Alberto Dalmaso, )
      Speeding up a query.  ("Hartman, Matthew", )
       Re: Speeding up a query.  (Anthony Presley, )
        Re: Speeding up a query.  ("Hartman, Matthew", )
       Re: Speeding up a query.  ("Albe Laurenz", )
        Re: Speeding up a query.  (Grzegorz Jaśkiewicz, )
       Re: Speeding up a query.  (Alberto Dalmaso, )
        Re: Speeding up a query.  ("Kevin Grittner", )
        Re: Speeding up a query.  (Tom Lane, )
       Re: Speeding up a query.  (Merlin Moncure, )
        Re: Speeding up a query.  ("Hartman, Matthew", )
       Re: Speeding up a query.  ("Hartman, Matthew", )
       Re: Speeding up a query.  (Simon Riggs, )
        Re: Speeding up a query.  ("Hartman, Matthew", )
 Re: performance with query  (Alberto Dalmaso, )
 Re: performance with query  (Alberto Dalmaso, )
  Re: performance with query  ("Kevin Grittner", )
   Re: performance with query  (Alberto Dalmaso, )
    Re: performance with query  ("Kevin Grittner", )
     Re: performance with query  (Alberto Dalmaso, )
      Re: performance with query  ("Kevin Grittner", )
       Re: performance with query  (Tom Lane, )
        Re: performance with query  ("Kevin Grittner", )

Alberto Dalmaso <> wrote:
> Il giorno mar, 16/06/2009 alle 15.58 +0100, Matthew Wakeling ha
> scritto:
>> On Tue, 16 Jun 2009, Alberto Dalmaso wrote:

>> > enable_hashjoin = off
>> > enable_nestloop = off
>> > enable_seqscan = off
>> > enable_sort = off
>>
>> Why are these switched off?
>>
> because of the need to pump up the performance of the complex query.

These really are meant primarily for diagnostic purposes.  As a last
resort, you could set them off right before running a problem query,
and set them back on again afterward; but you will be much better off
if you can cure the underlying problem.  The best chance of that is to
show us the plan you get with all turned on.

-Kevin


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