Home » Oracle » 1z0-052 » What are the two effects of this command?
A constraint in a table is defined with the INITIALLY IMMEDIATE clause. You executed the ALTER TABLE command with the ENABLE VALIDATE option to enable the constraint that was disabled.
What are the two effects of this command? (Choose two.)
A. It fails if any existing row violates the constraint.
B. It does not validate the existing data in the table.
C. It enables the constraint to be enforced at the end of each transaction.
D. It prevents insert, update, and delete operations on the table while the constraint is in the process of being enabled.
Correct Answer: AD
Explanation/Reference:
Explanation:
* Specify ENABLE if you want the constraint to be applied to the data in the table.
* ENABLE VALIDATE specifies that all old and new data also complies with the constraint. An enabled validated constraint guarantees that all data is and will continue to be valid (not B).
If any row in the table violates the integrity constraint, the constraint remains disabled and Oracle returns an error (A). If all rows comply with the constraint, Oracle enables the constraint. Subsequently, if new data violates the constraint, Oracle does not execute the statement and returns an error indicating the integrity constraint violation.
Note:
* Specify INITIALLY IMMEDIATE to indicate that Oracle should check this constraint at the end of each subsequent SQL statement.
Incorrect:
Not C: Specify INITIALLY DEFERRED to indicate that Oracle should check this constraint at the end of subsequent transactions.
Download Printable PDF. VALID exam to help you PASS.
|
|