me adv test [closed]

Question

Consider the following schedule:
S:R2(A), W1(B), W1(C), R3(B), R2(B), R1 (A), commit_1, R2(C), commit_2, W3(A), commit_3

How many given statements true about schedule(S)____.

(i) Schedule(S) is conflict serializable schedule.
(ii) Schedule(S) is allowed by 2PL.
(iii) Schedule(S) is strict recoverable schedule.
(iv) Schedule(S) is allowed by strict 2PL.

only 1 is correct as per my answer but in answer they have given 3

Comments

Refer this.

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2 statements are correct here (i) and (ii)

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according to me 1,2 and 4 are satisfied.

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To understand why 4th us not true refer the above link.

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Only 1,2 correct

This schedule can't be strict.