what is candidate key & super key
Answer / naresh
Cnadidate Key:
A Candidate Key (CK) is a column or group of columns that
uniquely describe every row in a table. The difficult thing
with this is that there may be exceptions in almost every
case. For instance, it is possible to have two people who
share the same name and birthdate but are really two
different people.
Super Key:
a superkey is a set of composite columns forming a key that
may be used to uniquely identify a row in a table
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