Question

Choose the correct statement regarding superkeys

(a) A superkey is an attribute or a group of multiple attributes that can uniquely identify a tuple

(b) A superkey is a tuple or a set of multiple tuples that can uniquely identify an attribute

(c) Every superkey is a candidate key

(d) A superkey is an attribute or a set of attributes that distinguish the relation from other relations

This question was posed to me during an interview.

This intriguing question comes from Introduction to the Relational Model topic in portion Introduction to Relational Model and Sql of RDBMS

Answer 1

Correct option is (a) A superkey is an attribute or a group of multiple attributes that can uniquely identify a tuple

The explanation: A superkey is an attribute or a set of multiple attributes that can uniquely identify a tuple. It is used to differentiate between tuples.