Re: CBO influences

From: DA Morgan <damorgan_at_psoug.org>
Date: Fri, 09 Sep 2005 22:25:09 -0700
Message-ID: <1126329859.958172@yasure>

Jonathan Lewis wrote:
> "DA Morgan" <damorgan_at_psoug.org> wrote in message
> news:1126306293.634107_at_yasure...
>

>>Jonathan Lewis wrote:
>>
>>>"EdStevens" <quetico_man_at_yahoo.com> wrote in message 
>>>news:1126294364.813025.287860_at_o13g2000cwo.googlegroups.com...
>>>
>>>
>>>>Bingo!  My partner had assured me that he had checked the
>>>>initialization parms and they were all identical.  When I looked at the
>>>>10053 trace where all the optimizer related parms were grouped together
>>>>I discovered that OPTIMIZER_INDEX_CACHING, OPTIMIZER_INDEX_COST_ADJ,
>>>>and OPTIMIZER_MAX_PERMUTATIONS were different.
>>>>
>>>
>>>There's a nice little feature in 10g
>>>that helps with that, the parameter
>>>list is split into the parameters
>>>with altered values and parameters
>>>with default values.
>>>
>>>Such a small change, but such a
>>>big help.
>>
>>Didn't the ISDEFAULT column exist in previous versions?

>
>
>
>
> Indeed,
>
> But we are talking about the 10053 trace file,
> and the current values for your session's
> parameters may not match the environment
> under which the trace was generated.

Thanks for the clarification.

One more, slightly related question, if I may.

Gathering system statistics I do not seem to be able to force a demo database to gather statistics for MBRC, MREADTIM, and SLAVETHR. I understand the last might be a bit difficult on a notebook used for classroom demo. But any help on any of this would be appreciated.

Thanks.

-- 
Daniel A. Morgan
http://www.psoug.org
damorgan_at_x.washington.edu
(replace x with u to respond)

Received on Sat Sep 10 2005 - 00:25:09 CDT