DBMS QUIZZ

What is the purpose of normalization in a database?

• The purpose of normalization is to reduce data redundancy and improve data integrity.

• To enhance the visual design of the database interface.

• To simplify database queries by merging tables.

• To increase data duplication for faster access.

Define the first normal form (1NF).

• A table is in first normal form (1NF) if it contains only atomic values and each record is unique.

• A table is in first normal form (1NF) if it has multiple values in a single column.

• A table is in first normal form (1NF) if it allows duplicate records.

• A table is in first normal form (1NF) if it contains non-atomic values.

What are the characteristics of the second normal form (2NF)?

• A table is in 2NF if it is in 1NF and all non-key attributes are fully functionally dependent on the primary key.

• A table is in 2NF if all attributes are dependent on a single non-key attribute.

• A table is in 2NF if it contains at least one foreign key.

• A table is in 2NF if it has no duplicate rows.

Explain the third normal form (3NF) and its importance.

• 3NF requires all attributes to be dependent on multiple keys.

• 3NF allows duplicate data to exist in a database.

• 3NF is primarily concerned with indexing and query performance.

• The third normal form (3NF) eliminates transitive dependencies, ensuring that all non-key attributes are only dependent on the primary key, which reduces redundancy and enhances data integrity.

What is a transaction in the context of a database?

• A transaction is a method for deleting data from a database.

• A transaction is a sequence of operations treated as a single unit of work in a database.

• A transaction is a backup of the database.

• A transaction is a type of database query.

List the ACID properties of a transaction.

• Atomicity, Consistency, Integrity, Reliability

• Atomicity, Consistency, Isolation, Durability

• Accuracy, Clarity, Simplicity, Flexibility

• Isolation, Durability, Stability, Availability

How does atomicity affect transactions?

• Atomicity allows partial transactions to be committed.

• Atomicity increases the speed of transaction processing.

• Atomicity guarantees that transactions are all-or-nothing, preserving data consistency.

• Atomicity requires transactions to be executed in sequence.

What is consistency in the context of ACID properties?

• Consistency means that all transactions are processed in the same order.

• Consistency ensures that a database remains in a valid state before and after a transaction.

• Consistency refers to the speed of database transactions.

• Consistency ensures that data is always encrypted during transactions.

Explain the significance of isolation in transactions.

• Isolation prevents all types of data corruption, regardless of the transaction type.

• Isolation allows transactions to run faster by reducing data checks.

• Isolation is significant in transactions as it maintains data integrity and consistency by preventing interference between concurrent transactions.

• Isolation is only important for single-user systems.

What does durability mean in terms of database transactions?

• Durability indicates that data can be lost during a transaction.

• Durability means that once a transaction is committed, it remains permanent, even in case of failures.

• Durability refers to the speed of transaction processing.

• Durability means that transactions can be rolled back at any time.