Explain the concept of Candidate Key with the help of a suitable examp

1.	Explain the concept of Candidate Key with the help of a suitable example.
Answer» A candidate key is a column, or set of columns, in a table that can uniquely identifies a tuple and is not null. Each table may have one or more candidate keys. It is eligible to be a Primary key. For example: In a table PERSON following are the columns (Aadhar number, PAN, Voter ID card no, Name, Date of birth, Address). Out of these Aadhar number, PAN, Voter ID card no are the candidate keys.

Explain the concept of Candidate Key with the help of a suitable example.

Answer»

A candidate key is a column, or set of columns, in a table that can uniquely identifies a tuple and is not null.

Each table may have one or more candidate keys. It is eligible to be a Primary key.

For example: In a table PERSON following are the columns (Aadhar number, PAN, Voter ID card no, Name, Date of birth, Address).

Out of these Aadhar number, PAN, Voter ID card no are the candidate keys.

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Explain the concept of Candidate Key with the help of a suitable example.

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