• TheV

MemberAug 30, 2011

What is the difference between SUPER KEY and UNIQUE KEY...!??

Please explain me the difference between the super key and unique key..!
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• MemberSep 2, 2011

UNIQUE KEY DEFINES ALL THE ROWS IN TABLE UNIQUELY .AND BASICALLY OCCURS ONLY SINGLE UNIQUE KEY IN ONE TABLE WHILE SUPER KEY UNIQUELY IDENTIFY A TUPLE AND NOT ALL THE ROWS i.e NO TWO TU PLES HAVE SAME ATTRIBUTES IN SUPER KEY
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• MemberSep 3, 2011

I am confused....!!! What is the difference between tuples and rows.
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• MemberSep 3, 2011

TheV
I am confused....!!! What is the difference between tuples and rows.
Tuple is nothing but another name of rows in database

Unique key is just a single attribute (Column) where as super key is a set of attributes

However both have same function ie to identify rows of a table uniquely
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• MemberSep 4, 2011

Thankyou Goyal....!

But In wikipedia the defination of unique is a one column or a set of columns which Identify the tuples or row uniquely.

First line, second sentence,,..<a href="https://en.wikipedia.org/wiki/Unique_key" target="_blank" rel="nofollow noopener noreferrer">Unique Key</a>
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• MemberSep 4, 2011

TheV
Thankyou Goyal....!

But In wikipedia the defination of unique is a one column or a set of columns which Identify the tuples or row uniquely.

First line, second sentence,,..<a href="https://en.wikipedia.org/wiki/Unique_key" target="_blank" rel="nofollow noopener noreferrer">Unique Key</a>
unique key may or may not contain set of column , while super key is basically a set of attributes
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