I need 14.26 ( a ) please a - Given the previous extension ( state), which of th

Question

I need 14.26 ( a ) please

a - Given the previous extension ( state), which of the following dependent cies may hold in the above relation? If the dependency cannot hold explain why by specfiying the tuples that cause the violation.

Consider the following relation: Given the previous extension (state), which of the following dependencies may hold in the above relation? If the dependency cannot explain why by specifying the tuples that cause the violation. A rightarrow B, B rightarrow C, C rightarrow B, B rightarrow A, C rightarrow A

Explanation / Answer

For X -> Y, for each value of X there should be unique value of Y.

a.) A->B; this dependency can't hold as tuple and tuple 2 gives different values of B on same value of A.

b.) b->C; this dependecyFor X -> Y, for each value of X there should be unique value of Y.

a.) A->B; this dependency can't hold as tuple 1 and tuple 2 gives different values of B on same value of A.

b.) B->C; this dependency holds true as for each value of B there is unique value.

c.) C->B; this dependency can't hold as tuple 1 and tuple 3 gives different values of B on same value of C.

d.) B->A; this dependency can't hold as tuple 1 and tuple 5 gives different values of A on same value of B.

e.) C->A;this dependency can't hold as tuple 1 and tuple 3 and tuple 5 gives different values of B on same value of C.

Hope it helps, do give your response.

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