Re: Selectivity of Indexes
Assume that you have the table EMP with the column DEPT_ID which has a bitmap index on it.
Originally posted by majub
Thanks for your reply. How can I collect the histogram for the bitmap indexed column? Please advise.
Thanks and regards
If you want to generate the table statistics on EMP and column statistics on the column DEPT_ID with maximum number of buckets being 90, you run:
Oracle has a default number of buckets equal to 75. For default value you simply run:
ANALYZE TABLE emp COMPUTE STATISTICS FOR TABLE FOR COLUMN dept_id SIZE 90;
ANALYZE TABLE emp COMPUTE STATISTICS FOR COLUMN dept_id;