Question

Consider a table named Students that has one primary key and three alternate keys. How many candidate keys does the table have?

Options

• 1

• 2

• 3

• 4

Answer 1

4

Explanation:

A candidate key is any attribute (or combination) that can uniquely identify a record in a table.

• One of the candidate keys is chosen as the primary key.
• The remaining ones are called alternate keys.

So, 

Total Candidate Keys

= Primary Key + Alternate Keys

= 1 + 3

Total Candidate Keys = 4