Consider the following database schedule with three transactions, T1, T2, and T3.
S = r2(A) r3(B) r1(B) w3(B) w2(A) w1(A) r3(A) w3(A);
where ri(A) and ri(B) denotes a read operation on data items A and B respectively and wi(A) and wi(B) denotes a write operation on data items A and B respectively by transaction Ti.1
S is serializable as T1 → T2 → T3
2
S is serializable as T1 → T3 → T2
3
S is serializable as T2 → T1 → T3
4
The schedule is not serializable