Transaction processing and ACID

What do you mean by consistent data in a database?

• All users view the same data.

• Providing different access levels to users.

• Information sharing between users.

• Customising data according to user's requirements.

What is meant by concurrency of a database?

• All changes in the database by different users are reflected to all users.

• All transactions of a database are independent.

• Each transaction is considered as a single entity.

• All of the above

Complete this sentence: A change in the database is called as …………………………..

• Transaction

• Data modification

• SQL query processing

• None of the above

Which of the following property states that an incomplete transaction is not recorded?

• Consistency

• Durability

• Atomicity

• Isolation

Which of the following is TRUE about the atomicity of a database?

• All transactions are considered to be a single entity.

• Incomplete changes are also recorded.

• Multiple operations of a transaction are considered to be a single entity.

What is durability of a database?

• During a power failure, all committed transactions are cancelled.

• During a power failure, few committed transactions are lost.

• During a power failure, all committed transactions survive.

True or False: Multiple transactions running at the same time must have the same results even when run sequentially.

• True

• False

Which of the following properties ensures that a database is in a valid state after the completion of a transaction?

• Durability

• Atomicity

• Isolation

• Consistency

Which of the following rule is NOT followed by a transaction in a database?

• All transactions are independent.

• All committed transactions survive a system crash.

• Multiple transactions might affect each other during run time.

• All of the above

Which of the following is a simple rule which states that only one person at a time can update an object in the database?

• Deadlock

• Record Locking

• Redundancy

• Serialisation