Re: Fed Up with being a DBA

> 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

personally I think that's BS - for one - RBO lacks a lot of features like function based index support,
partition pruning ...
Once you've set optimizer_index_cost_adj & optimizer_index_caching to values reflecting your
environment RBO never beats CBO !!!

"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...
>
>
> "Domenic G." <domenicg_at_hotmail.com> wrote in message
> news:c7e08a19.0309111612.69697120_at_posting.google.com...
> > I don't know about all of you, but I'm fed up with being a DBA and
> > working in the IT industry. I've been an Oracle DBA for several years
> > now and pride myself on knowing Oracle like the back of my hand.
> >
> > Here are my gripes ...
> >
> > - third party apps that run on Oracle and designed like junk.
> > - third party apps that insist on "GRANT DBA TO ..."
> > - schemas with FKs that aren't indexed (man do I hate that!)
> > - poorly written queries (EXISTS and IN are like cryptonite!)
> > - the COST based optimizer which outsmarts itself more often than not
> > so that I have to to /*+ ORDERED INDEX(a b) USE_NL (w x y z) */ to
> > achieve the same thing as /*+ RULE */
> > - schemas that still use CHAR(x)
> > - DBAs who use DBCA to create a DB and it adds in all that unwanted
> > JUNK!!
> >
> > Cheers ...
> > Domenic
>
>
Received on Fri Sep 12 2003 - 15:50:17 CDT