Re: optimizer parameters

Geomancer wrote:

<snip>

>
> From OTN, good advice:
>
> Rarely change CBO parameters. The CBO parameters are very dangerous
> because a single parameter change could adversely affect the
> performance of an entire enterprise. Changes to critical CBO
> parameters such as optimizer_mode, optimizer_index_cost_adj, and
> optimizer_index_caching should only be made after careful system
> testing.
>
> http://otn.oracle.com/oramag/webcolumns/2003/techarticles/burleson_cbo_pt1_pt2.html
Humbug! Apart from the "should be tested" bit.

Changing any parameter could cause the enterprise performance to change. Want another open door to kick in?!?

Remember the default shared pool of 3.5 MB? Suppose you never changed that, did you - come on!

-- 
Regards, Frank van Bortel