Re: Oracle 7.3 bit map index problem

Tim Nickason wrote:
> Hints won't work for me because the queries are generated by an OLAP client
> tool.
>

Create views with hints in them, eg:

create view fact_view as select

        /*+ index_combine( fact bitmap1  bitmap2... ) */ 
        * from fact;

create view table1_view as select
        /*+ index_combine( table1 bitmapA bitmapB... ) */
        * from table1;

I think the hints will accumulate when joins are performed between the two views. Do explain plans to verify. You could also create a single view with the join in it already.

Also, there are a few init.ora parameters to try:

v733_plans: "true" will enable btree-to-bitmap conversion (useful for mixing the two types of indexes in a query).

Here's an example:

12.........BITMAP OR
13...........BITMAP INDEX  SINGLE VALUE  BITMAP_DAY_IX
14...........BITMAP CONVERSION  FROM ROWIDS  
15.............SORT  ORDER BY
16...............INDEX  RANGE SCAN  BTREE_DATE_IX   ANALYZED

b_tree_bitmap_plans: true will enable btree to bitmap conversion even when no bitmap indexes are involved (eg doing two btree-to-bitmap conversions and ORing them) (probably not relevant here).

Good luck,

Kendall Received on Mon Oct 20 1997 - 00:00:00 CDT