Q#1: The main purpose of recovery techniques in DBMS is to:
(A) Maintain data consistency after system failure
(B) Encrypt data
(C) Normalize tables
(D) Delete old transactions
Answer: (A) Maintain data consistency after system failure
Q#2: Which of the following is a type of database failure?
(A) Transaction failure
(B) System crash
(C) Media failure
(D) All of the above
Answer: (D) All of the above
Q#3: Transaction failure occurs when:
(A) A transaction cannot complete due to some error
(B) System crashes
(C) Disk is damaged
(D) Database is encrypted
Answer: (A) A transaction cannot complete due to some error
Q#4: System crash refers to:
(A) Operating system or DBMS failure
(B) Transaction rollback
(C) Hardware working normally
(D) Successful commit
Answer: (A) Operating system or DBMS failure
Q#5: Media failure refers to:
(A) Physical damage to storage devices
(B) Transaction rollback
(C) System crash
(D) Normal transaction execution
Answer: (A) Physical damage to storage devices
Q#6: Recovery technique must ensure:
(A) Atomicity
(B) Consistency
(C) Durability
(D) All of the above
Answer: (D) All of the above
Q#7: Log-based recovery uses:
(A) Transaction logs to redo or undo operations
(B) Backup only
(C) Locks
(D) Concurrency control
Answer: (A) Transaction logs to redo or undo operations
Q#8: Undo operation is used to:
(A) Rollback incomplete transactions
(B) Commit changes
(C) Lock data
(D) Encrypt database
Answer: (A) Rollback incomplete transactions
Q#9: Redo operation is used to:
(A) Reapply committed changes after crash
(B) Undo changes
(C) Delete transactions
(D) Normalize tables
Answer: (A) Reapply committed changes after crash
Q#10: Before-image in log records:
(A) State of data before transaction update
(B) State of data after update
(C) Transaction ID only
(D) Commit time only
Answer: (A) State of data before transaction update
Q#11: After-image in log records:
(A) State of data after transaction update
(B) State before update
(C) Transaction ID only
(D) Timestamp only
Answer: (A) State of data after transaction update
Q#12: Checkpointing in recovery is used to:
(A) Reduce recovery time by storing consistent state
(B) Delete old logs
(C) Encrypt data
(D) Lock tables
Answer: (A) Reduce recovery time by storing consistent state
Q#13: Deferred update recovery technique:
(A) Updates are applied to database only after transaction commits
(B) Updates are applied immediately
(C) Logs are ignored
(D) Database is locked
Answer: (A) Updates are applied to database only after transaction commits
Q#14: Immediate update recovery technique:
(A) Updates are applied to database immediately, before commit
(B) Updates are deferred
(C) Logs are ignored
(D) Database is read-only
Answer: (A) Updates are applied to database immediately, before commit
Q#15: Shadow paging avoids:
(A) Writing logs
(B) Database updates
(C) Locking
(D) Transactions
Answer: (A) Writing logs
Q#16: Media recovery is required when:
(A) Disk crashes or storage is damaged
(B) Transaction fails
(C) System is normal
(D) Database is consistent
Answer: (A) Disk crashes or storage is damaged
Q#17: The main components of recovery are:
(A) Undo, redo, and checkpoint
(B) Locks and timestamps
(C) Normalization and encryption
(D) Logging only
Answer: (A) Undo, redo, and checkpoint
Q#18: Undo/Redo logging ensures:
(A) Atomicity and durability
(B) Consistency only
(C) Isolation only
(D) Deadlock prevention
Answer: (A) Atomicity and durability
Q#19: Recovery manager is responsible for:
(A) Managing recovery after failures
(B) Encrypting data
(C) Normalizing tables
(D) Managing users
Answer: (A) Managing recovery after failures
Q#20: Transaction rollback is required in recovery when:
(A) Transaction is incomplete
(B) Transaction is committed
(C) Database is consistent
(D) Data is encrypted
Answer: (A) Transaction is incomplete
Q#21: Redo logging is performed to:
(A) Ensure durability after system crash
(B) Undo uncommitted changes
(C) Lock tables
(D) Normalize tables
Answer: (A) Ensure durability after system crash
Q#22: Undo logging is performed to:
(A) Rollback uncommitted transactions
(B) Commit changes
(C) Encrypt database
(D) Delete tables
Answer: (A) Rollback uncommitted transactions
Q#23: Checkpointing may include:
(A) Writing all dirty pages to disk
(B) Storing transaction log
(C) Updating database consistency
(D) All of the above
Answer: (D) All of the above
Q#24: Shadow paging maintains:
(A) Two copies of database pages
(B) One copy only
(C) Only transaction logs
(D) Only checkpoints
Answer: (A) Two copies of database pages
Q#25: Recovery after system crash involves:
(A) Redoing committed transactions and undoing uncommitted transactions
(B) Only undo operations
(C) Only redo operations
(D) Ignoring transactions
Answer: (A) Redoing committed transactions and undoing uncommitted transactions
Q#26: Media failure recovery typically uses:
(A) Backups and transaction logs
(B) Only checkpoints
(C) Only locks
(D) Immediate updates
Answer: (A) Backups and transaction logs
Q#27: Atomicity in recovery ensures:
(A) Either all operations of a transaction are applied or none
(B) Only committed transactions are applied
(C) Isolation of transactions
(D) Database is normalized
Answer: (A) Either all operations of a transaction are applied or none
Q#28: Recovery manager interacts with:
(A) Transaction manager and storage manager
(B) Users only
(C) Locks only
(D) Encryption manager
Answer: (A) Transaction manager and storage manager
Q#29: Undo/Redo logging requires:
(A) Before and after images of updated data
(B) Only before image
(C) Only after image
(D) No images
Answer: (A) Before and after images of updated data
Q#30: Main goal of recovery techniques is:
(A) Ensure data integrity, atomicity, and durability after failures
(B) Encrypt database
(C) Normalize tables
(D) Reduce storage only
Answer: (A) Ensure data integrity, atomicity, and durability after failures