Problem
Consider a schedule S1 with five transactions T1, T2, T3 T4 and T5 as follows: S1: R1(x); W2(x); R3(x); R1(y); R4(z); W2(y); R1(v); W3(v); R4(v); W4(y); W5(y); W5(z);
i. (17%) Is S conflict-serializable ? Hint: To read easily, write the schedule in a table that has one column per transaction, and one line per action. Then read the schedule and spot the conflicting pairs of actions. Use this information to create the precedence graph.
ii. (3%) If S is conflict-serializable, what is a serial schedule S' that is conflict-equivalent to S (i.e. that has the same result as S)?