Question

Which of the following should be a primary key?
a) A person's last name
b) An employee's salary
c) A customer's ID number
d) A salesperson's region.
​

Answer 1

c) A customer's ID number should be a primary key.

• In the field of computer studies, the primary key represents a unique identification number which serves as a unique  for something in a table or a list.

• For example, in a customer table, each customer can have a certain unique identification number. The field of unique identification number will be the primary key.

Hence, the correct option is c)  A customer's ID number