22319 database management mcq Unit 5: Database security and Transaction Processing

2. Which of the following makes the transaction permanent in the database?  a) View
b) Commit
c) Rollback
d) Flashback
Answer: b Explanation: Commit work commits the current transaction.

3. In order to undo the work of transaction after last commit which one should be used? a) View
b) Commit
c) Rollback
d) Flashback
Answer: c "Explanation: Rollback work causes the current transaction to be rolled back; that is, it undoes all the updates performed by the SQL statements in the transaction."

4. Consider the following action: TRANSACTION..... Commit; ; ROLLBACK What does Rollback do? a) Undoes the transactions before commit
b) Clears all transactions
c) Redoes the transactions before commit
d) No action
Answer: d "Explanation: Once a transaction has executed commit work, its effects can no longer be undone by rollback work."

5. In case of any shut down during transaction before commit which of the following statement is done automatically? a) View
b) Commit
c) Rollback
d) Flashback
Answer: c "Explanation: Once a transaction has executed commit work, its effects can no longer be undone by rollback work."

"6. In order to maintain the consistency during transactions, database provides" a) Commit
b) Atomic
c) Flashback
d) Retain
Answer: b "Explanation: By atomic, either all the effects of the transaction are reflected in the database, or none are (after rollback)."

7. Transaction processing is associated with everything below except a) Conforming an action or triggering a response
b) Producing detail summary or exception report
c) Recording a business activity
d) Maintaining a data
Answer: a

8. A transaction completes its execution is said to be a) Committed
b) Aborted
c) Rolled back
d) Failed
Answer: a Explanation: A complete transaction always commits.

9. Which of the following is used to get back all the transactions back after rollback? a) Commit
b) Rollback
c) Flashback
d) Redo
Answer: c

10. will undo all statements up to commit? a) Transaction
b) Flashback
c) Rollback
d) Abort
Answer: c Explanation: Flashback will undo all the statements and Abort will terminate the operation.

11. Consider money is transferred from (1)account-A to account-B and (2) account-B to account-A. Which of the following form a transaction? a) Only 1
b) Only 2
c) Both 1 and 2 individually
d) Either 1 or 2
Answer: c Explanation: The term transaction refers to a collection of operations that form a single logical unit of work.

12. A transaction is delimited by statements (or function calls) of the form                       a) Begin transaction and end transaction
b) Start transaction and stop transaction
c) Get transaction and post transaction
d) Read transaction and write transaction
Answer: a Explanation: The transaction consists of all operations executed between the begin transaction and end transaction.

13. Identify the characteristics of transactions a) Atomicity
b) Durability
c) Isolation
d) All of the mentioned
Answer: d "Explanation: Because of the above three properties, transactions are an ideal way of structuring interaction with a database."

14. Which of the following has “all-or-none” property? a) Atomicity
b) Durability
c) Isolation
d) All of the mentioned
Answer: a "Explanation: Either all operations of the transaction are reflected properly in the database, or none are."

15. The database system must take special actions to ensure that transactions operate properly without interference from concurrently executing database statements. This property is referred to as a) Atomicity
b) Durability
c) Isolation
d) All of the mentioned
Answer: c "Explanation: Even though multiple transactions may execute concurrently, the system guarantees that, for every pair of transactions Ti and Tj, it appears to Ti that either Tj finished execution before Ti started or Tj started execution after Ti finished."

16. The property of a transaction that persists all the crashes is a) Atomicity
b) Durability
c) Isolation
d) All of the mentioned
Answer: b "Explanation: After a transaction completes successfully, the changes it has made to the database persist, even if there are system failures."

17.states that only valid data will be written to the database. a) Consistency
b) Atomicity
c) Durability
d) Isolation
Answer: a "Explanation: If for some reason, a transaction is executed that violates the database’s consistency rules, the entire transaction will be rolled back and the database will be restored to a state consistent with those rules."
 
18. Transaction processing is associated with everything below except
a) Producing detail summary or exception reports
b) Recording a business activity
c) Confirming an action or triggering a response
d) Maintaining a data
Answer: c Explanation: Collections of operations that form a single logical unit of work are called transactions.

19. The Oracle RDBMS uses the statement to declare a new transaction start and its properties. a) BEGIN
b) SET TRANSACTION
c) BEGIN TRANSACTION
d) COMMIT
Answer: b Explanation: Commit is used to store all the transactions.

20.means that the data used during the execution of a transaction cannot be used by a second transaction until the first one is completed. a) Consistency
b) Atomicity
c) Durability
d) Isolation
Answer: d "Explanation: Even though multiple transactions may execute concurrently, the

system guarantees that, for every pair of transactions Ti and Tj, it appears toTi that either Tj finished execution before Ti started or Tj started executionafter Ti finished."

21. Collections of operations that form a single logical unit of work are called                       a) Views
b) Networks
c) Units
d) Transactions
Answer: d Explanation: Collections of operations that form a single logical unit of work are called transactions. A database system must ensure proper execution of transactions.

22. The “all-or-none” property is commonly referred to as                     a) Isolation
b) Durability
c) Atomicity
d) None of the mentioned
Answer: c Explanation: The all or none policy is commonly referred to as atomicity. It ensures that a work is either completed or not completed and there are no intermediate stages.

23. Which of the following is a property of transactions? a) Atomicity
b) Durability
c) Isolation
d) All of the mentioned Answer: d

24. Execution of translation in isolation preserves the of a database a) Atomicity
b) Consistency
c) Durability
d) All of the mentioned
Answer: b Explanation: Execution of translation in isolation preserves the consistency of a database. It ensures that no other transaction is running concurrently.

25. Which of the following is not a property of a transaction? a) Atomicity
b) Simplicity
c) Isolation
d) Durability
Answer: b "Explanation: Simplicity is not a property of a transaction. Atomicity, Isolation, Durability are all parts of ACID properties."

26. Which of the following systems is responsible for ensuring durability? a) Recovery system
b) Atomic system
c) Concurrency control system
d) Compiler system
Answer: a "Explanation: The recovery system is responsible for the maintenance of durability. In addition, it also ensures atomicity."

27. Which of the following systems is responsible for ensuring isolation? a) Recovery system
b) Atomic system
c) Concurrency control system
d) Compiler system
Answer: c Explanation: The concurrency control system is responsible for ensuring isolation in a database system.

28. State true or false: Information residing in the volatile storage does not usually survive system crashes a) True
b) False
Answer: a Explanation: Information residing in the volatile storage does not usually survive system crashes but the information in stable storage can survive system crashes efficiently.

29. A transaction that has not been completed successfully is called as                 a) Compensating transaction
b) Aborted transaction
c) Active transaction
d) Partially committed transaction
Answer: b Explanation: Aborted transaction is a state after the transaction has been rolled back and the database has been restored to the state prior to the transaction.

30. Which of the following is not a transaction state? a) Active
b) Partially committed
c) Failed
d) Compensated
Answer: d "Explanation: Compensated is not a transaction state. But active, partially committed and failed are different states of a transaction."

31. The execution sequences in concurrency control are termed as                    a) Serials
b) Schedules
c) Organizations
d) Time tables
Answer: b Explanation: The execution sequences in concurrency control are known as schedules.

32. The scheme that controls the interaction between executing transactions is called as              a) Concurrency control scheme
b) Multiprogramming scheme
c) Serialization scheme
d) Schedule scheme
Answer: a Explanation: The scheme that controls the interaction between executing transactions is called as concurrency control scheme.

33. What is true about data security? A. Data security is the protection of programs and data in computers and communication systems against unauthorized access
B. It refers to the right of individuals or organizations to deny or restrict the collection and use of information
C. Data security requires system managers to reduce unauthorized access to the systems by building physical arrangements and software checks
. D. All of the above
Ans: D Explanation: All of the above statement are true.

34. Which of the following are data security considerations? A. Backups
B. Archival Storage
C. Disposal of Data
D. All of the above
Ans: D Explanation: All of the above are data security consideration.

35. Which of the following is most used rule for backup? A. 4-2-1 Rule
B. 3-2-1 Rule
C. 4-3-2 Rule
D. 4-3-1 Rule
Ans : B Explanation: To use the Backup 3-2-1 Rule is very popular.

36. In 3-2-1 rule 2 represents? A. copies of our data
B. different formats
C. off-site backup
D. None of the above
Ans : B "Explanation: Two different formats, i.e., hard drive+tape backup or DVD (short term)+flash drive"

37. Which of the following is not a recovery technique? A. Deferred update
B. Immediate update
C. Two-phase commit
D. Recovery management
Answer: C

38. Checkpoints are a part of A. Recovery measures
B. Security measures
C. Concurrency measures
D. Authorization measures
Answer: C

"39. ....... deals with soft errors, such as power failures." A. system recovery
B. media recovery
C. database recovery
D. failure recovery Answer: D

40. ........... is an essential part of any backup system. A. Filter
B. Recovery
C. Security
D. Scalability
Answer: C

41. Media recovery deals with ........... A. disk errors
B. hard errors
C. system errors
D. power failures
Answer: A

"42. For a backup/restore system, ............. is a prerequisite for service in a enterprise." A. Filter
B. Recovery
C. Security
D. Scalability Answer: D

43. Failure recovery and media recovery fall under ........ A. transaction recovery
B. database recovery
C. system recovery
D. value recovery
Answer: C

44. The .......... consists of the various applications and database that play a role in a backup and recovery strategy. A. Recovery Manager environment
B. Recovery Manager suit
C. Recovery Manager file
D. Recovery Manager database
Answer: A

45. In which the database can be restored up to the last consistent state after the system failure? A. Backup
B. Recovery
C. Both
D. None
Answer: B

46. A ........... is a block of Recovery Manager(RMAN)job commands that is stored in the recovery catalogue. A. recovery procedure
B. recovery block
C. stored block
D. stored script Answer: D

"47. In log based recovery, the log is sequence of ........." A. filter
B. records
C. blocks
D. numbers
Answer: B

48. The enrolling of a database in a recovery catalogue is called ......... A. set up
B. registration
C. start up
D. enrolment
Answer: B

49. .......... is an alternative of log based recovery. A. Disk recovery
B. Shadow paging
C. Dish shadowing
D. Crash recovery
Answer: B

50. Most backup and recovery commands in ........... are executed by server sessions. A. Backup Manager
B. Recovery Manager
C. Backup and Recovery Manager
D. Database Manager
Answer: B

51. ........ systems typically allows to replace failed disks without stopping access to the system. A. RAM
B. RMAN
C. RAD
D. RAID Answer: D

"52. An ......... is an exact copy of a single datafile, archived redo log file, or control file." A. image copy
B. datafile copy
C. copy log
D. control copy
Answer: A

"53. .......... known as memory-style error correcting-code(ECC) organization, employs parity bits." A. RAID level 1
B. RAID level 2
C. RAID level 3
D. RAID level 4
Answer: B

54. The remote backup site is sometimes called the .......... site. A. primary
B. secondary
C. ternary
D. None of the above
Answer: B

55. EXP command is used........... A. to take Backup of the Oracle Database
B. to import data from the exported dump file
C. to create Rollback segments
D. to create Schedule
. Answer: A

56. The simplest approach to introducing redundancy is to duplicate every disk is called ..... A. mirroring
B. imaging
C. copying
D. All of the above
Answer: A