how to add a bitmap index with b-tree index

[huchen]

Hello,

I want to add a index to a large table
table_1(state_code, customer_num, other_col)

I want to add an index like :

CREATE BITMAP INDEX IDX_bitmap_1
ON table_1(state_code, customer_num)
TABLESPACE base_index ;

As you know, state_code is only 52, but this table has billions of rows with unique customer_num

I want state_code is bitmap index, but within each code, customer_num is b-tree indexed

How can I do it?
thank you

 

[Dagon]

You can't. An index is either b-tree or bitmap. It can't be both. Bitmap indexes are generally on single columns rather than concatenated because they are meant to be used in combination with other bitmap indexed columns.

Why do you think you need an index like that ? What benefit do you think it would give ?