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hemant kumar
Define candidate key, alternate key, composite key.
1 Answer(s)      4 years and a month ago
Posted in : SQL


Define candidate key, alternate key, composite key.


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November 15, 2010 at 5:45 PM


Hi,

Here is the answer,

candidate key- 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.

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

composite key- A key formed by combining at least two or more columns is called composite key.

Thanks.



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