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Question

Given the following relation instance.

x y z
1 4 2
1 5 3
1 6 3
3 2 2

Which of the following functional dependencies are satisfied by the instance? (GATE CS 2000)

a.

XY -> Z and Z -> Y

b.

YZ -> X and Y -> Z

c.

YZ -> X and X -> Z

d.

XZ -> Y and Y -> X

Answer: (b).YZ -> X and Y -> Z

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Q. Given the following relation instance. x y z 1 4 2 1 5 3 1 6 3 3 2 2 Which of the...

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