waht is the difference between primary key and super key?
Answer Posted / kishore singh bisht
primary key is a uniquely identified key,in primary key we use only a single attribute to identify a row.......
example:- roll no. of an student, employee id etc.
primary key=unique+not null.
and super key is a combination of two or more attributes which make the uniqueness.......
ex:-name+d.o.b+contact no...
these three attributes make the uniqueness by which we can easily identify.............
Is This Answer Correct ? | 11 Yes | 5 No |
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