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Question

Consider the following schedules involving two transactions.

S1 : r1(X) ; r1(Y) ; r2(X) ; r2(Y) ; w2(Y) ; w1(X)
S2 : r1(X) ; r2(X) ; r2(Y) ; w2(Y) ; r1(Y) ; w1(X)

Which one of the following statements is correct with respect to above?

a.

Both S1 and S2 are conflict serializable.

b.

Both S1 and S2 are not conflict serializable.

c.

S1 is conflict serializable and S2 is not conflict serializable.

d.

S1 is not conflict serializable and S2 is conflict serializable.

Answer: (d).S1 is not conflict serializable and S2 is conflict serializable.

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Q. Consider the following schedules involving two transactions. S1 : r1(X) ; r1(Y) ; r2(X) ; r2(Y) ; w2(Y) ; w1(X) S2 : r1(X) ; r2(X) ; r2(Y) ; w2(Y) ; r1(Y) ; w1(X) Which one...

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