Multiple choice

Which of the following constraints should you use to ensure that the combination of values in the JOB and TITLE columns in the EMPLOYEE table is unique?

  1. NULL

  2. CHECK

  3. UNIQUE

  4. FOREIGN KEY

  5. _

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

When a column or set of columns is defined as unique to the database management system, the system verifies that each set of value is unique before assigning the constraint.