Re: search on front of compound key

You are correct, the OtherNonUniqueKey index is redundant and can safely be dropped. Actually, it reduces performance on inserts, deletes, and some updates, as both indexes must be maintained.

Tim

"robert" <gnuoytr_at_rcn.com> wrote in message news:da3c2186.0306261421.3a52c224_at_posting.google.com...
> i can't find a thread which answers the question:
> does oracle (8.1.x) benefit from having multiple compound
> keys?
>
> NonUniqueKey -> col1 + col2 + col3
> OtherNonUniqueKey -> col1 + col2
>
> a where clause -> where col1 = 'A' and col2 = 'B'
>
> other databases i've used would retrieve (based on the
> physical architecture of their index stores) just as fast
> on NonUniqueKey; OtherNonUniqueKey is completely redundant.
>
> thanks,
> robert
Received on Fri Jun 27 2003 - 02:26:46 CEST