Define candidate key, alternate key, composite key?
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Answer Posted / kumaresan chandran
A candidate key is one that can identify each row
of a table uniquely. Generally a candidate key becomes the
primary key of the table. If the table has more than one
candidate key, one of them will become the primary key, and
the rest are called alternate keys.
A key formed by combining at least two or more
columns is called composite key.
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