Database Management System

Unit 5: Concurrency control technique

  • Q1). What do you mean by concurrency control techniques?
  • Q2). Write the comparison between single user and multi-user system.
  • Q3). What do you mean by Transaction?
  • Q4). Write the ACID property of Transcation.
  • Q5). What is the need of concurrency control.
  • Q6). Explain the lost update problem and dirty read problem.
  • Q7). Describe the problem faced when concurrent transaction are executing in uncontrolled manner. Give an example and explain.
  • Q8). Explain the working of locking technique in concurrency control. What benefits does Rigorous two-phase locking provide? How does it compare with other forms of two-phase locking?
  • Q9). What is two phase locking? Describe with the help of an example. Will two phase lockin g result in deadlock? Justify your answer with the help of an example . Discuss the recovery with concurrent transactions also.
  • Q10). What is two-phase locking protocol? List the salient features of strict two-phase locking protocol. Explain with a suitable example how cascading rollbacks can be avoided using strict two-phase locking.
  • Q11). Write brief note about basic timestamp ordering.
  • Q12). Discuss the important phases of optimistic concurrency control techniques. Write the advantages of using optimistic concurrency control techniques.
  • Q13). What is multi version schemes of concurrency control? Discuss with the help of and example. Discuss the various time stamping protocols for concurrency control also.
  • Q14). Explain the working of various time stamping protocols for concurrency control.
  • Q15). What do you mean by Multiple Granularity ? Discuss with a suitable example . Discuss the validation based protocols also with a suitable example.
  • Q16). Describe granularity locking. How does granularity of data items affect the performance of concurrency control?
  • Q17). Discuss the working of multiple granularity schemes in concurrency control.
  • Q18). Explain the UNDO/REDO recovery algorithm.
  • Q19). Explain the UNDO/NO-REDO recovery algorithm.
  • Q20). Explain the architecture of Oracle Database system.
  • Q21). Discuss the Oracle data dictionary.
  • Q22). Write and explain the various Oracle Process.
  • Q23). What do you mean by PL/SQL block. Explain it with syntax.
  • Q24). What do you mean by cursor? Write the various command to control cursor. Explain with example.