Re: EXPLAIN Plan

On Mon, 02 Oct 2006 20:41:08 GMT, "Dereck L. Dietz" <dietzdl_at_ameritech.net> wrote:

>Earlier today my manager sent an EXPLAIN PLAN to a number of us for help
>with a query. In the EXPLAN PLAN there was an INDEX RANGE SCAN which the
>off-site DBA said was caused by the table not being analyzed.
>
>The INDEX RANGE SCAN was using an index - maybe not the one I'd expect but
>nonetheless was using an index on the table being EXPLAINED.
>
>Am I missing something or does what the DBA not really make sense?
>

The index range scan was using an index: yeah, that's the purpose of an index range scan isn't it.
You might be missing something, but we are missing something too. We would need more information to verify the assertion of the DBA. The cardinality of this particular predicate (which you withheld from us) could have been so high, an analysis would have caused a more efficient full table scan.
But who can tell, as you don't share the statement, don't share the plan, don't share cardinality info.

--
Sybrand Bakker, Senior Oracle DBA