For each of the following schedules, draw the precedence graph and state if the schedule is...

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For each of the following schedules, draw the precedence graph and state if the schedule is conflict serializable. If the schedule is conflict serializable, give one possible equivalent serial schedule. (Ri means transaction i reads an item and Wi writes an item. Ci means transaction i commits.) a) R1(A);R4(A);W1(A);W3(B);R2(A);R2(B); W2(C);R4(B);R4(C);R2(D);R3(E);C1;C2;C3;C4; b) R1(A);W1(A);R2(A);R2(B);W3(B);W2(C);R4(A);R4(B);R2(D);R3(E);C1;C2;C3;C4; For the following schedule, insert the appropriate locks (shared and exclusive) into the schedule following the Strict 2PL protocol. Also explain what happens as the scheduler executes the schedule. Note that, if a transaction blocks because of an operation, the transaction with the next operation in the schedule will continue. If you have a deadlock, you need to chose a transaction to abort, release its locks and then the schedule will continue. The aborted transaction will start again later. When a transaction unblocks, it resumes its operations. Write the actual executed schedule. R1(A); R2(B); R3(C);W1 (B);W2(C); W3(D);C1;C2;C3; For each of the following schedules, draw the precedence graph and state if the schedule is conflict serializable. If the schedule is conflict serializable, give one possible equivalent serial schedule. (Ri means transaction i reads an item and Wi writes an item. Ci means transaction i commits.) a) R1(A);R4(A);W1(A);W3(B);R2(A);R2(B); W2(C);R4(B);R4(C);R2(D);R3(E);C1;C2;C3;C4; b) R1(A);W1(A);R2(A);R2(B);W3(B);W2(C);R4(A);R4(B);R2(D);R3(E);C1;C2;C3;C4; For the following schedule, insert the appropriate locks (shared and exclusive) into the schedule following the Strict 2PL protocol. Also explain what happens as the scheduler executes the schedule. Note that, if a transaction blocks because of an operation, the transaction with the next operation in the schedule will continue. If you have a deadlock, you need to chose a transaction to abort, release its locks and then the schedule will continue. The aborted transaction will start again later. When a transaction unblocks, it resumes its operations. Write the actual executed schedule. R1(A); R2(B); R3(C);W1 (B);W2(C); W3(D);C1;C2;C3;

Answer rating: 100% (QA)

STEP BY STEP ANSWER A Let the 4 transactions be named as T1 T2 T3 and T4 The given schedule in tabular form is Timestamp T1 T2 T3 T4 1 R1A 2 R4A 3 W1A 4 W3B 5 R2A 6 R2B 7 W2C 8 R4B 9 R4C 10 R2D 11 R3E ... View the full answer