Consider the transactions T1, T2, and T3 and the schedules S1 and S2 given below. T1: r1(X); r1(Z); w1(X); w1(Z) T2: r2(Y); r2(Z); w2(Z) T3: r3(Y); r3(X); w3(Y) S1: r1(X); r3(Y); r3(X); r2(Y); r2(Z); w3(Y); w2(Z); r1(Z); w1(X); w1(Z)S2: r1(X); r3(Y); r2(Y); r3(X); r1(Z); r2(Z); w3(Y); w1(X); w2(Z); w1(Z) Which one of the following statements about the schedules is TRUE ?

Only S2 is conflict-serializable.

Only S1 is conflict-serializable.

Only S2 is conflict-serializable.

Both S1 and S2 are conflict-serializable.

Neither S1 nor S2 is conflict-serializable.

Consider the transactions T1, T2, and T3 and the schedules S1 and S2 g

1.	Consider the transactions T1, T2, and T3 and the schedules S1 and S2 given below. T1: r1(X); r1(Z); w1(X); w1(Z) T2: r2(Y); r2(Z); w2(Z) T3: r3(Y); r3(X); w3(Y) S1: r1(X); r3(Y); r3(X); r2(Y); r2(Z); w3(Y); w2(Z); r1(Z); w1(X); w1(Z) S2: r1(X); r3(Y); r2(Y); r3(X); r1(Z); r2(Z); w3(Y); w1(X); w2(Z); w1(Z) Which one of the following statements about the schedules is TRUE ?
A.	Only S1 is conflict-serializable.
B.	Only S2 is conflict-serializable.
C.	Both S1 and S2 are conflict-serializable.
D.	Neither S1 nor S2 is conflict-serializable.
Answer» B. Only S2 is conflict-serializable.

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