Assignments on Advanced Topics in Database Management (PGIT 203)

(Transaction- Concurrency Control – Recovery)

1. Write the definition of Transaction.

2. List the ACID properties. Explain the usefulness of each.

3. Draw the Transaction State Diagram & Explain.

4. What do you mean by Schedule?

5. What is conflict serializability? Describe with a suitable example.

6. What is view serializability? Describe with a suitable example.

7. Explain precedence Graph.

8. Which are recoverable schedules?

9. What is the role of Lock Manager?

10. Show that two-phase locking protocol ensures conflict serializability, and that transactions can be serialized according to their lock points.

11. What is a cascade less schedule?

12. Why cascadelessness of a schedule is desirable?

13. Are there any circumstances under which it would be desirable to allow noncascadeless schedules? Explain your answer.

14. What is phantom phenomenon?

15. Show that two-phase locking protocol ensures conflict serializability, and that transactions can be serialized according to their lock points.

16. When a transaction is rolled back under timestamp ordering, it is assigned a new timestamp. Why can it not simply keep its old timestamp?

17. Write about Graph based protocols.

18. How Deadlocks are prevented in concurrency control mechanism?

19. Describe wait-for graph.

20. What is Time-stamp based protocol?

21. What is validation based protocol?

22. Write about different types of failures.

23. Write the difference between deferred database modification & immediate database modification.

24. Write the role of checkpoints in recovery.

25. What is Write Ahead Logging (WAL) rule?