Define candidate key, alternate key, composite key?

Answer Posted / palanivel

primary key:- The attribute or combination of attributes
that uniquely identifies a row or record.

Foreign Key:- an attribute or combination of attribute in a
table whose value match a primary key in another table.

Composite key:- A primary key that consistsof two or more
attributes is known as composite key

candidate key:- is a column in a table which has the
ability to become a primary key.

Alternate Key:- Any of the candidate keys that is not part
of the primary key is called an alternate key.

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