I am facing a strange oracle problem. We have a table with three columns . The first column is a primary key combination of second columna nd the third column.

We have created three indexes.
1. primary key index on first column
2. index on second column
3. index on the third column.

We are doing simple select query on second and third column.
During this query, Oracle is not using the index that is already presend on the table. It is doing a full table scan.

By the way, we have cascade delete on the first column.

Can some help or throw some light on this ?