Columns A, B, C of my table are indexed together as one index. One of the queries uses only B and C in the where clause. The query is doing a full table scan on the table and is very slow. If I add column A to the where clause, it executes extremely fast and uses the combined index.

What can be done in such a scenario? Is creating a separate index just for B and C the only way out? Can I not trick my query into using the super index (A, B, C) without using column A in the query?