Consider the following schedule: S: r1(x) r4(y) w1(z) r4(z) w2(y) r3(y) w1(x) w2(x) w3(z) w4(x) w3(x)…
The schedule is view serializable but not conflict serializable. Its conflict graph has the cycle T4 → T2 → T4, from the operations on y and x. The serial order T1, T4, T2,…
Choose your answer
Consider the following schedule:
S: r1(x) r4(y) w1(z) r4(z) w2(y) r3(y) w1(x) w2(x) w3(z) w4(x) w3(x)
Which of the following statements are true?
Answer and explanation
Correct answer B
The schedule is view serializable but not conflict serializable. Its conflict graph has the cycle T4 → T2 → T4, from the operations on y and x. The serial order T1, T4, T2, T3 preserves the initial reads, the reads-from relationships and the final writers, so it is view equivalent to the schedule.
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Telangana SET (TG SET)