Let S be the following schedule of operations of three transactions T1, T2 and T3 in a relational database system:R2(Y), R1(X), R3(Z), R1(Y), W1(X), R2(Z), W2(Y), R3(X), W3(Z)Consider the statements P and Q below:P: S is conflict-serializable.Q: If T3 commits before T1 finishes, then S is recoverable.Which one of the following choices is correct?

Let S be the following schedule of operations of three transactions T1

1.	Let S be the following schedule of operations of three transactions T1, T2 and T3 in a relational database system:R2(Y), R1(X), R3(Z), R1(Y), W1(X), R2(Z), W2(Y), R3(X), W3(Z)Consider the statements P and Q below:P: S is conflict-serializable.Q: If T3 commits before T1 finishes, then S is recoverable.Which one of the following choices is correct?
A.	P is true and Q is false.
B.	Both P and Q are true.
C.	P is false and Q is true.
D.	Both P and Q are false.
Answer» B. Both P and Q are true.

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