Understanding DBMS Concepts

What is the purpose of database normalization?

• To enhance security by restricting data access.

• The purpose of database normalization is to minimize redundancy and dependency by organizing fields and table relationships.

• To increase data duplication for faster access.

• To simplify complex queries by merging tables.

Explain the first normal form (1NF).

• First Normal Form (1NF) is a property of a relation in a relational database that ensures all columns contain atomic values and each row is unique.

• First Normal Form (1NF) is only applicable to non-relational databases.

• 1NF requires that all columns can contain multiple values.

• First Normal Form (1NF) allows duplicate rows in a table.

What are functional dependencies in the context of normalization?

• Functional dependencies are relationships that define how one attribute uniquely determines another attribute in a database.

• Functional dependencies are only applicable to primary keys.

• Functional dependencies describe the physical storage of data.

• Functional dependencies are irrelevant in database design.

Describe the difference between 2NF and 3NF.

• 2NF focuses on eliminating duplicate data; 3NF focuses on data integrity.

• 2NF eliminates partial dependencies; 3NF eliminates transitive dependencies.

• 2NF requires all attributes to be dependent on the primary key; 3NF allows some dependencies.

• 2NF is concerned with normalization; 3NF is about denormalization.

What is a transaction in a database management system?

• 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.

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

List the ACID properties of transactions.

• Atomicity, Consistency, Isolation, Durability

• Atomicity, Consistency, Isolation, Availability

• Atomicity, Consistency, Integrity, Durability

• Atomicity, Consistency, Isolation, Reliability

What is the significance of the commit operation in transaction management?

• The commit operation rolls back a transaction to its initial state.

• The commit operation is used to delete all changes made during a transaction.

• The commit operation temporarily saves changes without making them permanent.

• The commit operation finalizes a transaction, making all changes permanent and ensuring data integrity.

Explain the concept of rollback in transactions.

• Rollback is the process of permanently deleting a transaction from the database.

• Rollback is the process of reverting a transaction to its previous state to maintain data integrity in case of errors.

• Rollback is a method to speed up transaction processing by skipping steps.

• Rollback is the act of committing a transaction to finalize changes.

What is a deadlock in transaction management?

• A deadlock is a situation where transactions are executed in parallel without any waiting.

• A deadlock is a situation in transaction management where two or more transactions are unable to proceed because each is waiting for the other to release resources.

• A deadlock is when a single transaction holds all resources and completes its execution.

• A deadlock occurs when a transaction completes successfully without any issues.

How can database normalization improve data integrity?

• It allows for more flexible data storage without structure.

• It increases data redundancy and complexity.

• It prevents all types of data loss and corruption.

• Database normalization improves data integrity by eliminating redundancy and ensuring data dependencies are correctly enforced.