Re: Oracle 7.3.2.3 not using Indexes

Stephen A. Rodgers wrote:
>
> Okay, I've been having a wierd problem with Oracle 7.3.2.3 on Solaris
> 2.5 where it appears that Oracle just stops using certain indexes from
> time to time. This does not appear to have anything to do with Cost
> Based Optimizer as I can switch to Rule mode and the indexes still won't
> be used in queries when they should be. The tables are analyzed with
> compute statistics, and the indexes are usually rebuilt automatically
> after direct path loads.
>

I assume your access rights to your indexes are correct (remember you can have different access rights on data and index!).

If none of the indexes are used, try the hint /*+ index (ALIAS INDEXNAME) */ in the regarding select statement.

If the wrong index is used, this may come from the age the index has. If the optimizer (both rule and cost based) can choose between two indexes and both indexes seem equally suiting to it, it will use the newer index. So check the sequence your indexes are created after your direct load. By the way, which execution plan are you told from the explain plan command?

-- 
Martin Haltmayer