Define candidate key, alternate key, composite key?
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Answer Posted / raju
candidate key:-A candidate key uniquely identifies the rows
in a table.there can be more than 1 candidate key in a
table, in which one should be a primary key.
alternate key:-In the candidate key the key which is not
primary key is the alternate key.
composite key:- A key formed bythe combination of 2 or more
columns is the composite key.
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