Re: Fed Up with being a DBA

Joel Garry wrote:

>"Alan" <alan_at_erols.com> wrote in message news:<bjt4db$mouue$1_at_ID-114862.news.uni-berlin.de>...
>
>
>>I haven't run any tests to prove this, but I was told by Someone Who Should
>>Know (a certfied Oracle Instructor) that CBO can't optimize a query any
>>better than a _properly_ optimized RBO query. If that is true, and one is
>>adept at optimizing RBO, then why go to CBO (except for reallly certain
>>cases such as large queries that are too time consuming to optimize
>>manually)? Just asking, not trying to make a point...
>>
>>
>
>CBO can optimize _some_ queries better than RBO. To get an idea which
>ones, look at all the hints. However, the OP has a good point, and
>that is, those are rarely relevant to OLTP queries in commercial
>packages that have been wrung out for years.
>
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On this I'll agree. But one must remember that those commercial packages were, for the most part, written a decade ago, have little more advanced than v7 code, and desparately need work.

My statement was that CBO will equal or outpeform RBO if in the hands of someone that knows how to work with it. Same thing goes for playing golf or picking a good wine. Too many people are still thinking v7-8 when they should be thinking v9-10. And likely it is those same people that will be complaining soon that their jobs were off-shored.

-- 
Daniel Morgan
http://www.outreach.washington.edu/ext/certificates/oad/oad_crs.asp
http://www.outreach.washington.edu/ext/certificates/aoa/aoa_crs.asp
damorgan_at_x.washington.edu
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