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Question

Which of the following is NOT a superkey in a relational schema with attributes V, W, X, Y, Z and primary key V Y ?

a.

V X Y Z

b.

V W X Z

c.

V W X Y

d.

V W X Y Z

Answer: (b).V W X Z

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Q. Which of the following is NOT a superkey in a relational schema with attributes V, W, X, Y, Z and primary key V Y ?

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