Exhibit： View the Exhibit to see the data in the emp table. You created a PRIMARY KEY constraint on the empno column of the emp table， and the constraint is not deferred. Which two statements are true in this scenario？ （）
- ANo index would be created or used in this case.
- BA unique index on the empno column would be created.
- CA CHECK constraint would be enforced on the empno column.
- DA NOT NULL constraint would be enforced on the empno column.
- EA bitmap unique index would be created on the empno column.