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Question

Which of the following statements is TRUE?

D1: The decomposition of the schema R(A,B,C) into R1(A,B) and R2(A,C) is always lossless.
D2: The decomposition of the schema R(A,B,C,D,E) having AD→B, C→DE, B→AE, AE→C into R1(A,B,D) and R2(A,C,D,E) is lossless.

a.

Both D1 and D2

b.

Neither D1 and D2

c.

Only D1

d.

Only D2

Answer: (d).Only D2

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Q. Which of the following statements is TRUE? D1: The decomposition of the schema R(A,B,C) into R1(A,B) and R2(A,C) is always lossless. D2: The decomposition of the schema...

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