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Question

Let R ={A, B, C, D, E, F} be a relation schema with the following dependencies C→F,E→A,EC→D,A→B
Which of the following is a key for R ?

a.

CD

b.

EC

c.

AE

d.

AC

Answer: (b).EC

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Q. Let R ={A, B, C, D, E, F} be a relation schema with the following dependencies C→F,E→A,EC→D,A→B Which of the following is a key for R ?

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