Evaluate the following ALTER TABLE statement: ALTER TABLE orders SET UNUSED
order_date; Which statement is true?
A.
The ORDER_DATE column should be empty for the ALTER TABLE command to
execute successfully.
B.
After executing the ALTER TABLE command, you can add a new column called
ORDER_DATE to the ORDERS table.
C.
ROLLBACK can be used to get back the ORDER_DATE column in the ORDERS table.
D.
The DESCRIBE command would still display the ORDER_DATE column.
Explanation: