Gate2019 cs Q21

21Consider the following two statements about database transaction schedules:
I. Strict two-phase locking protocol generates conflict serializable schedules that are also recoverable.
II. Timestamp-ordering concurrency control protocol with Thomas’ Write Rule can generate view serializable schedules that are not conflict serializable.
Which of the above statements is/are TRUE?

Option : C
Explanation :
I. Strict 2PL guaranteed conflict serializable because of 2PL condition and also strict recoverable.
II. Thomas Write timestamp ordering ensures serializable. Thomas write rule timestamp ordering allowed to execute schedule which is view equal serial schedule based on timestamp ordering.

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