Re: Execution plan changed after upgrade from 7.3.9 to 8.2.3

From: Michael Fuhr
Subject: Re: Execution plan changed after upgrade from 7.3.9 to 8.2.3
Date: ,
Msg-id: 20070313101117.GA98241@winnie.fuhr.org
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In response to: Execution plan changed after upgrade from 7.3.9 to 8.2.3  (<>)
Responses: Re: Execution plan changed after upgrade from 7.3.9 to 8.2.3  (<>)
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Execution plan changed after upgrade from 7.3.9 to 8.2.3  (<>, )
 Re: Execution plan changed after upgrade from 7.3.9 to 8.2.3  (Michael Fuhr, )
  Re: Execution plan changed after upgrade from 7.3.9 to 8.2.3  (<>, )
   Re: Execution plan changed after upgrade from 7.3.9 to 8.2.3  (Richard Huxton, )
    Re: Execution plan changed after upgrade from 7.3.9 to 8.2.3  (<>, )
     Re: Execution plan changed after upgrade from 7.3.9 to 8.2.3  ("Dave Dutcher", )
      Re: Execution plan changed after upgrade from 7.3.9 to 8.2.3  (<>, )
       Re: Execution plan changed after upgrade from 7.3.9 to 8.2.3  ("Dave Dutcher", )
     Re: Execution plan changed after upgrade from 7.3.9 to 8.2.3  (Richard Huxton, )
   Re: Execution plan changed after upgrade from 7.3.9 to 8.2.3  (Alvaro Herrera, )
    Re: Execution plan changed after upgrade from 7.3.9 to 8.2.3  (<>, )
     Re: Execution plan changed after upgrade from 7.3.9 to 8.2.3  (Alvaro Herrera, )
      Re: Execution plan changed after upgrade from 7.3.9 to 8.2.3  (<>, )
       Re: Execution plan changed after upgrade from 7.3.9 to 8.2.3  (Tom Lane, )
        Re: Execution plan changed after upgrade from 7.3.9 to 8.2.3  (<>, )

On Tue, Mar 13, 2007 at 09:19:47AM +0100,  wrote:
> Is there an option in the 8.2.3 to change in order to have the same
> execution plan than before ?

Let's see if we can figure out why 8.2.3 is choosing a bad plan.
Have you run ANALYZE on the tables in 8.2.3?  Could you post the
query and the complete output of EXPLAIN ANALYZE (preferably without
wrapping) for both versions?

--
Michael Fuhr


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