Re: SW vendor insists on RBO

"Peter van Rijn" <pgm.van.rijnRM_at_THIShccnet.nl> wrote in message news:aotscg$pge$1_at_news.hccnet.nl...
> Niall,
>
> You don't have to convince me of the desirablity to use CBO. I offered our
> vendor to do part of the analysis if problems arise when changing from RBO
> to CBO.

I did come over a bit evangelical didn't I, sorry.

>
> My post was meant to find out if one might expect more unexpected errors
> (because of bad design of course ;-) ), comparable to the ORA-1722 we had.
I
> *was* expecting differences with respect to performance, but received
weird
> errors in stead.

I think what I was trying to say is that one shouldn't *expect* an Oracle error message from using the CBO instead of the RBO, and that if one does get error messages it will most likely be down to the app rather than the optimiser. In this case for example if the index didn't exist the RBO would use the same access path and you'd get the same error.

--
Niall Litchfield
Oracle DBA
Audit Commission UK
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