Database Modeling and Design MCQs with Answers
Practice important Database Modeling and Design MCQs with answers and explanations.
Chapter: 23
Q321:
What does the Durability property of a transaction guarantee?
A. The system can recover data after a failure
B. The transaction is isolated from other transactions
C. The database will remain consistent
D. The transaction will not be rolled back
Correct Answer:
A
Chapter: 23
Q322:
If a transaction violates a database constraint, what property is compromised?
A. Durability
B. Isolation
C. Consistency
D. Atomicity
Correct Answer:
C
Chapter: 23
Q323:
Which of the following scenarios demonstrates the Consistency property?
A. Updating a record without any data validation
B. Performing operations that affect multiple tables simultaneously
C. Ensuring no constraint violations during a transaction
D. Executing transactions in isolation
Correct Answer:
C
Chapter: 23
Q324:
What should happen to a transaction if a system failure occurs midway?
A. The system should restart the transaction
B. The transaction should be committed partially
C. The system should rollback the transaction to its initial state
D. The transaction should be executed manually
Correct Answer:
C
Chapter: 23
Q325:
Fill in the blank: The ________ property of transactions ensures that the database is in a consistent state before and after the transaction.
A. Atomicity
B. Isolation
C. Consistency
D. Durability
Correct Answer:
C
Chapter: 23
Q326:
Fill in the blank: A transaction's effects are permanently in place in the system even if the system fails or restarts, ensuring ________.
A. Consistency
B. Isolation
C. Durability
D. Atomicity
Correct Answer:
C
Chapter: 23
Q327:
Fill in the blank: The property that allows the system to handle simultaneous transactions as if each were the only transaction is called ________.
A. Isolation
B. Atomicity
C. Consistency
D. Durability
Correct Answer:
A
Chapter: 24
Q328:
What problem occurs when multiple transactions update the same data but one transaction's updates are overwritten?
A. Lost Update Problem
B. Uncommitted Data
C. Deadlock
D. Granularity Issue
Correct Answer:
A
Chapter: 24
Q329:
Which problem happens when one transaction reads data updated by another transaction that has not yet committed?
A. Uncommitted Data
B. Lost Update Problem
C. Deadlock
D. Granularity Issue
Correct Answer:
A
Chapter: 24
Q330:
What is the main purpose of using locks in a database system?
A. To speed up transaction processing
B. To ensure data consistency
C. To reduce database size
D. To increase query execution time
Correct Answer:
B
Chapter: 24
Q331:
What does a read lock do in a multi-user database system?
A. Prevents other users from reading the data
B. Allows other users to read the data but prevents writing
C. Prevents any access to the data
D. Allows only one user to update the data
Correct Answer:
B
Chapter: 24
Q332:
Which level of lock involves locking an entire table?
A. Database Lock
B. File Lock
C. Table Lock
D. Row Lock
Correct Answer:
C
Chapter: 24
Q333:
What level of lock is the most commonly used and supported by major database vendors?
A. Column Lock
B. Row Lock
C. Table Lock
D. File Lock
Correct Answer:
B
Chapter: 24
Q334:
Which type of lock prevents other transactions from accessing the data until the current transaction is completed?
A. Shared Lock
B. Exclusive Lock
C. Read Lock
D. Write Lock
Correct Answer:
B
Chapter: 24
Q335:
Fill in the blank: The problem of ________ occurs when a transaction reads data that has been updated by another transaction which has not yet committed.
A. Uncommitted Data
B. Lost Update
C. Deadlock
D. Granularity Issue
Correct Answer:
A
Chapter: 24
Q336:
Fill in the blank: The level of lock where only a particular column or multiple columns are locked is called ________.
A. Row Lock
B. File Lock
C. Column Lock
D. Table Lock
Correct Answer:
C
Chapter: 24
Q337:
Fill in the blank: A ________ Lock allows multiple users to read the same data simultaneously but prevents any updates until the lock is released.
A. Shared
B. Exclusive
C. Read
D. Write
Correct Answer:
A
Chapter: 24
Q338:
Fill in the blank: To prevent dirty data in concurrent transactions, database systems use ________.
A. Locks
B. Indexes
C. Caches
D. Cursors
Correct Answer:
A
Chapter: 24
Q339:
Which of the following is NOT a level of lock granularity in a database?
A. Column Lock
B. Row Lock
C. Transaction Lock
D. Table Lock
Correct Answer:
C
Chapter: 24
Q340:
What is one method for detecting deadlocks in a database system?
A. Use a priority-based locking system
B. Increase the number of locks allowed
C. Set a lock wait time limit
D. Allow all transactions to execute concurrently
Correct Answer:
C