Which of the following schedules are allowed by strict 2pl with shared and xclusive locks -
- r1(A); r2(B); r3(C); w1(B); c1; w2(C); c2; w3(D); c3
- r1(A); r2(B); r3(C); r1(B); r2(C); r3(D); c3; w1(C); c1; w2(D); c2
- r1(A); r2(B); r3(C); w1(B); w2(C); w3(A); c1; c2; c3
- None of the above
The solution given is 3). But how can the solution be 3) as it is not conflict serializable?
Is this the correct procedure to determine if a schedule is strict 2pl -
Check for conflict serializablility and strict recoverability and both must be satisfied.
In the above 1) and 2) satisfy conflict serializablility and strict recoverability. Then which is the correct solution?