Define candidate key, alternate key, composite key?

Answer Posted / sanjay p sonar

Candidate key:-A candidate key is unique. We may say that
candidate key is another name of primary key. We can have
more than one candidate key. From which we have to choose
one as a primary key.

Alternate key:-The Candidate key other than primary key is
Alternate key. We can have more than one Alternate keys.

Composite key:- When we combine more than 1 column by key
then that key is called Composite key

Clustered Key:- When we combine more than 1 column to form
Primary key then it will become Cluster key.

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