Question

Which one of the following items would be the best primary key for a table containing...

Which one of the following items would be the best primary key for a table containing information about customers?

customer ID

customer full name

customer email address

customer phone number

Homework Answers

Answer #1

Solution:

1) Customer ID,

A customer ID is a particular number or alphabets, It describes information about customers. Each ID represents seperate information.

Rest of the options are wrong, Because if we are choosing name as primary key, There is possibility for same names. It will leads to confusion. Inorder to avoid this, Try to use customer ID as primary key. It will reduce these types of confusions. If we are choosing email id or mobile number as a primary key, We will get only limited information about a customer.

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