Which of the following constraints cannot be added to an existing table with the ADD clause of the ALTER TABLE command?
A) CHECK
B) UNIQUE
C) NOT NULL
D) none of the above

Question

Which of the following constraints cannot be added to an existing table with the ADD clause of the ALTER TABLE command?​
A) ​CHECK
B) ​UNIQUE
C) ​NOT NULL
D) ​none of the above

Quizplus · Accepted Answer

The Answer of Which of the following constraints cannot be added to an existing table with the ADD clause of the ALTER TABLE command?​
A) ​CHECK
B) ​UNIQUE
C) ​NOT NULL
D) ​none of the above

Which of the Following Constraints Cannot Be Added to an Existing