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Consider the following scenario involving three transactions and two data items:...
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Consider the following scenario involving three transactions and two data items:T1 locks data item A in exclusive mode and then requests an exclusive lock on B.T2 locks data item B in exclusive mode and then requests an exclusive lock on C.T3 locks data item C in exclusive mode and then requests an exclusive lock on A.If two-phase locking protocol was used, which is/are of the following statements are true:
i) Deadlock will not occur because each transaction holds only one lock at a time.ii) Deadlock will occur involving T1, T2, and T3 due to a circular wait condition.iii) No deadlock will occur if the DBMS uses a wait-die scheme with timestamps such that T1 < T2 < T3.iv) The scenario violates the two-phase locking protocol, so deadlock is impossible.