Re: optimizer parameters

From: ed lewis <>
Date: Tue, 26 Apr 2011 06:05:06 -0400
Message-ID: <BACF631400AB4ACE9C3850B28C22BA5D_at_CATHY>

Hi Dave,

    Yes, I can trace the query in both environments, and compare the results.

    I also doubt that the vendor will push to get these parameters implemented, knowing that they will be accountable. In the meantime, I plan to go forward, and handle each sql query on an individual basis.     

    I'm still curious though, if anyone has modified, and implemented these parameters. If you were installing a new application, would modifying these parameters be a general practice, even if it was not a vendor recommendation ?



  • Original Message ----- From: "David Mann" <> To: <> Sent: Monday, April 25, 2011 11:06 AM Subject: Re: optimizer parameters

> >Stephane,

>>    Thanks for you input.
>>    I did change these parameters on the session level,
>>but it did not change the original plan for this
>>particular query. So even making these changes,
>>does not guarantee the desired or expected results.
>>As been mentioned, the focus should be on the
>>actual query.
>>    Also, this particular query takes 14 seconds on prod,
>>but 6 seconds in dev. They both generate the same plan.
>>The environments also differ in data volume and user
>>activity. The vendor is questioning why the times are
>>not comparable.

> So the plans are the same - I would let the vendor know what you found
> - especially that their recommendation did not solve the issue. I
> avoid "Big Knob" tuning on established systems as well. Unless the
> client has a way to test the system and determine if any performance
> got worse because of the changes.
> In the meantime anything stopping you from tracing execution (with
> WAIT info captured) on Dev and Prod to see differences in what the
> query is spending its time on?
> -Dave
> --
> Dave Mann
> - Database Stuff -
> --

Received on Tue Apr 26 2011 - 05:05:06 CDT

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