Re: Index Usage Question

Good morning, Tanel and Ryan:

I have been able to get Oracle to rely on the index I require.

A secondary index on the table also seemed to be interferring with Oracle's selection of the best way to select. After removing the extraneous index and resetting the statistics, the performance seems to have come back into line (we now seem to be bound through the network, but that's another project.

Thanks for your input,

Mark.

"Tanel Poder" <tanel@@peldik.com> wrote in message news:3ef7aae4$1_1_at_news.estpak.ee...
>
> Hi!
>
> > When the query is executed for one or two ioid values , the proper index
> is
> > used. However when a third point is addes to the retrieval a full table
> > scan is initiated (this is a problem as the table currently contains
> > ~60,000,000 records). Ideally it would always (or nearly always) use
the
> > index.
> >
> > The index is unique on the ioid and reportdatentime columns of the
table.
>
> Have you recently analyzed your indexes and tables?
> What are the values for your parameters optimizer_index_cost_adj,
> optimizer_index_caching and db_file_multiblock_read_count ?
>
> Tanel.
>
>
>
Received on Tue Jun 24 2003 - 09:55:06 CDT