UGC-NET | UGC NET CS 2018 July – II | Question 65
Consider the following schedules involving two transactions.
S1: r1 (X) ; r 1 (Y) ; r 2 (X) ; r 2 (Y) ; w 2 (Y) ; w1 (X)
S2: r1 (X) ; r 2 (X) ; r 2 (Y) ; w 2 (Y) ; r 1 (Y) ; w1 (X)
Which one of the following statements is correct with respect to above ?
(A) Both S1 and S 2 is conflict serializable.
(B) Both S1 and S2are not conflict serializable.
(C) S1 is conflict serializable and S 2 is not conflict serializable.
(D) S 1is not conflict serializable and S 2 is conflict serializable.
Explanation: Precedence graph for S1 and S2 are given below respectively:
Therer is cycle in S1 but no cycle in S2.
So, option (D) is correct.
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