Re: performance with query - Mailing list pgsql-performance

From Tom Lane
Subject Re: performance with query
Date
Msg-id 15480.1245166290@sss.pgh.pa.us
Whole thread Raw
In response to Re: performance with query  (Alberto Dalmaso <dalmaso@clesius.it>)
Responses Re: performance with query  (Alberto Dalmaso <dalmaso@clesius.it>)
List pgsql-performance
Alberto Dalmaso <dalmaso@clesius.it> writes:
> Il giorno mar, 16/06/2009 alle 15.58 +0100, Matthew Wakeling ha scritto:
>>> 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.

That is *not* the way to improve performance of a query.  Turning off
specific enable_ parameters can be helpful while investigating planner
behavior, but it is never recommended as a production solution.  You
have already found out why.

            regards, tom lane

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