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Higher Study | DBMS | Concurrency Control

Which of the following concurrency control protocols ensure both conflict serializability and freedom from deadlock? I. 2-phase locking II. Time-stamp ordering
For a multi-processor architecture, In which protocol a write transaction is forwarded to only those processors that are known to possess a copy of newly altered cache line?
 Concurrency control in RDBMS is important for which of the following reasons ?
In a database system, unique timestamps are assigned to each transaction using Lamport’s logical clock. Let TS(T1) and TS(T2) be the timestamps of transactions T1 and T2 respectively. Besides, T1 holds a lock on the resource R, and T2 has requested a conflicting lock on the same resource R. The following algorithm is used to prevent deadlocks in the database system assuming that a killed transaction is restarted with the same timestamp. If TS(T2) < TS(T1) then T1 is killed else T2 waits. Assume any transaction that is not killed terminates eventually. Which of the following is TRUE about the database system that uses the above algorithm to prevent deadlocks?
Consider 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?
Which of the following concurrency control protocol ensures both conflict serializability and free from deadlock?
Let transaction T1 has obtained a shared mode lock S on data item Q and transaction T2 has obtained an exclusive mode lock X on data item R  Consider the following statement. I: T1 can read Q but cannot write Q. II. T2 can read R but cannot write R. Which of the above statements is / are valid?
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