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? (Choose two.)
Exhibit:
A. No index would be created or used in this case.
B. A unique index on the empno column would be created.
C. A CHECK constraint would be enforced on the empno column.
D. A NOT NULL constraint would be enforced on the empno column.
E. A bitmap unique index would be created on the empno column.
Answer: BD
The Oracle Database implementation of the primary key constraint guarantees that the following statements are true:
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No two rows have duplicate values in the specified column or set of columns.
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The primary key columns do not allow nulls.
