Question

In an employee table to include the attributes whose value always have some value which of the following constraint must be used?

(a) Null

(b) Not null

(c) Unique

(d) Distinct

I got this question during a job interview.

My query is from Null Values Operations topic in division SQL : Queries, Constraints and Triggers of Database Management

Answer 1

Correct option is (b) Not null

To explain: Not null constraint removes the tuples of null values.