Differentiate between key and superkey, Database Management System

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Differentiate between Key and superkey?

Key and superkey - A key a single attribute or a combination of two or more attributes of an entity set in which is used to identify one or more instances (rows) of the set (table). If we add a few additional attributes to a primary key then in which augmented key is known as super key. Thus, the primary key is the minimum super key.


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