Test S

Question

This schedule is:

A) Recoverable and conflict serializable
B) Irrecoverable and conflict serializable
C) Recoverable and non-conflict serializable
D) Irrecoverable and non-conflict serializable

 

Comments

is it option D ?

---

i am getting option (c)

for conflict serializability there is loop between t1 ,t2, t3 so it will not conflict serializable and for recoverable we know for every W(X) and R(X) pair W(X) will commit first after that R(X) commit.so all the W(X) and R(X) pair maintain the basic property of recoverable schedule.

---

Yes it is not conflict seroalizable and it is recoverable.

Answer 1

Its option D

Because Dirty Read exist (W(x) --> R(x)) in T3 --> T4, So Its non-recoverable.

 S: W3(x) W2(x) R4(x) W1(x) R3(x)

For this schedule through conflicts in precedence graph cycle exist ,So its not conflict serizable.