Master Database Normalization Techniques for Optimal Database Design

Question 1

Which of the following is the primary objective of database normalization?

Accepted Answer

Eliminating data redundancy and improving data integrity

Answer

Reducing data storage requirements

Answer

Enhancing data security

Answer

Minimizing the number of tables in a database

Question 2

Which dependency violation is addressed by 2NF?

Accepted Answer

Partial dependencies

Answer

Transitive dependencies

Answer

Multivalued dependencies

Answer

Inclusion dependencies

Question 3

Which of the following is NOT a benefit of database normalization?

Accepted Answer

Increased data insertion and update overhead

Answer

Enhanced data retrieval efficiency

Answer

Reduced data redundancy

Answer

Improved data integrity

Question 4

In a relational database, what is a candidate key?

Accepted Answer

A minimal set of attributes that uniquely identifies each row

Answer

The largest attribute in the relation

Answer

Any attribute that can be used to identify a row

Answer

The attribute with the smallest cardinality

Question 5

Which of the following operations is used to break down a relation into smaller relations with reduced redundancy?

Accepted Answer

Normalization

Answer

Denormalization

Answer

Refactoring

Answer

Optimization

Question 6

Which normal form ensures that all non-key attributes are non-transitively functionally dependent on the primary key?

Accepted Answer

Boyce-Codd normal form (BCNF)

Answer

Second normal form (2NF)

Answer

Third normal form (3NF)

Answer

Fourth normal form (4NF)

Question 7

Which of the following techniques is used to combine two or more relations into a single relation?

Accepted Answer

Denormalization

Answer

Normalization

Answer

Refactoring

Answer

Optimization

Question 8

Which of the following is a typical scenario where denormalization is beneficial?

Accepted Answer

Enhancing query performance

Answer

Enforcing data integrity

Answer

Reducing data redundancy

Answer

Simplifying transaction management

Question 9

**Functional Dependency:**

Which of the following correctly defines functional dependency?

Accepted Answer

A relationship where one attribute's value uniquely determines another's.

Answer

A rule that applies only to primary and foreign keys.

Answer

A concept that is eliminated through normalization.

Answer

An irrelevant factor in database design.

Question 10

Summarize the key characteristics and applicability of first normal form (1NF), second normal form (2NF), and third normal form (3NF).

Accepted Answer

1NF eliminates repeating groups, 2NF removes partial dependencies, and 3NF eliminates transitive dependencies.

Answer

1NF ensures atomic values, 2NF enforces referential integrity, and 3NF prevents update anomalies.

Answer

1NF requires unique keys, 2NF prohibits null values, and 3NF guarantees data consistency.

Question 11

What is the primary goal of database normalization?

Accepted Answer

To minimize data duplication

Answer

To enhance data reliability

Answer

To boost data security

Answer

To reduce storage requirements

Question 12

To achieve Second Normal Form (2NF), a table must satisfy 1NF and:

Accepted Answer

Eliminate partial dependencies

Answer

Have a single primary key

Answer

Have no duplicate rows

Answer

Have no missing values

Question 13

Which normalization form requires the removal of transitive dependencies?

Accepted Answer

3NF

Answer

1NF

Answer

2NF

Answer

4NF

Question 14

Consider the following table:

Customer (CustomerID, CustomerName, Address, PhoneNumber, OrderID)

Which option highlights a potential normalization issue in this table?

Accepted Answer

OrderID represents a partial dependency

Answer

CustomerID is not a primary key

Answer

PhoneNumber is not unique

Answer

CustomerName lacks a data type

Question 15

In the context of database normalization, what is a surrogate key?

Accepted Answer

A unique identifier not derived from the table's data

Answer

A primary key based on a natural attribute

Answer

A foreign key referencing another table

Answer

An attribute used for grouping rows

Question 16

Consider the relation Order (Order ID, Customer ID, Product ID, Quantity, Order Date). Is this relation in 3NF?

Accepted Answer

No, due to the partial dependency of Quantity on Customer ID

Answer

Yes

Answer

No, due to the transitive dependency of Order Date on Customer ID

Answer

No, due to the composite primary key

Question 17

Which step is NOT part of the database normalization process?

Accepted Answer

Normalizing to Boyce-Codd Normal Form (BCNF)

Answer

Identifying functional dependencies

Answer

Creating a dependency diagram

Answer

Decomposing the relation

Question 18

When selecting an appropriate normalization form, which factor should be considered?

Accepted Answer

The specific requirements of the database application

Answer

Always normalizing to the highest possible form

Answer

Using only 1NF and 2NF

Answer

There are no specific guidelines.

Question 19

What is the primary objective of database normalization?

Accepted Answer

Minimize data redundancy

Answer

Ensure data correctness

Answer

Improve query performance

Answer

Simplify data structure

Question 20

Which condition is NOT required for a table to be in 1st Normal Form (1NF)?

Accepted Answer

The table must have a defined primary key

Answer

Each row must have a unique identifier

Answer

Each column must contain only non-composite values

Answer

There must be no repeating groups within a column

Question 21

Which normalization level ensures that no non-trivial functional dependencies exist?

Accepted Answer

Boyce-Codd Normal Form (BCNF)

Answer

1st Normal Form (1NF)

Answer

2nd Normal Form (2NF)

Answer

3rd Normal Form (3NF)

Question 22

Which tool is used to represent dependencies between attributes in a database table?

Accepted Answer

Functional Dependency Diagram

Answer

Entity-Relationship Diagram

Answer

Data Flow Diagram

Answer

Use Case Diagram

Question 23

How does normalization enhance database query performance?

Accepted Answer

Accelerates query speed by minimizing redundant data

Answer

Slows down query speed by requiring more table joins

Answer

Has no effect on query performance

Question 24

Which of the following is a limitation of Boyce-Codd Normal Form (BCNF)?

Accepted Answer

Handles multi-valued dependencies

Answer

Eliminates insertion, update, and deletion anomalies

Answer

Improves data integrity

Answer

Reduces data redundancy

Question 25

Which of the following is NOT a benefit of normalization?

Accepted Answer

Increased data redundancy

Answer

Improved data integrity

Answer

Simplified data retrieval

Answer

Reduced data storage space

Question 26

Consider the following relation:
`Customers(customer_id, name, address, order_date)`
Is this relation in 2NF?

Accepted Answer

No

Answer

The relation is already in 3NF

Answer

Yes

Answer

Cannot be determined

Question 27

A lossless join is one that:

Accepted Answer

Preserves all data from the input tables

Answer

Eliminates duplicate rows from the input tables

Answer

Restricts data based on a condition

Question 28

Denormalization may be considered when:

Accepted Answer

Performance optimization is a priority

Answer

Data security is the main objective

Answer

Data integrity is the top priority

Answer

Data consistency is the primary concern

Question 29

A potential drawback of normalization includes:

Accepted Answer

Increased dependency on join operations

Answer

Improved data integrity

Answer

Reduced data redundancy

Answer

Simplified data retrieval

Question 30

The primary goal of database normalization is to:

Accepted Answer

Eliminate data redundancy and inconsistencies

Answer

Simplify database design solely

Answer

Enhance data security

Answer

Improve database performance solely

Question 31

The key difference between 2NF and 3NF is that:

Accepted Answer

3NF eliminates transitive dependencies, which 2NF does not

Answer

2NF requires a primary key, which 3NF does not

Answer

2NF removes repeating groups, which 3NF does not

Question 32

The purpose of using a composite key is to:

Accepted Answer

Uniquely identify a record when a single attribute is insufficient

Answer

Simplify table design solely

Answer

Improve performance solely

Question 33

A potential drawback of normalization is:

Accepted Answer

Increased data redundancy

Answer

Reduced storage space solely

Answer

Enhanced data consistency solely

Answer

Improved performance solely

Question 34

The Boyce-Codd Normal Form (BCNF) is defined as:

Accepted Answer

A normal form that eliminates all non-key dependencies

Answer

A normal form that is equivalent to 3NF

Answer

A normal form that is stricter than 3NF

Question 35

Database denormalization may be appropriate when:

Accepted Answer

Performance is critical and data redundancy is acceptable

Answer

The database is in 3NF

Answer

The database is in 1NF

Question 36

To achieve 3NF, a table must first be in:

Accepted Answer

2NF

Answer

4NF

Answer

5NF

Answer

1NF

Question 37

Consider a table with the attributes {student_id, name, class_id, grade}. What is the candidate key for this table?

Accepted Answer

{student_id}

Answer

{name, class_id}

Answer

{student_id, name}

Answer

{class_id, grade}

Question 38

Which of the following is NOT a guideline for database normalization?

Accepted Answer

Avoid creating tables with too few rows

Answer

Minimize the number of null values

Answer

Eliminate repeating groups of data

Answer

Ensure that each table is cohesive and represents a single entity

Question 39

Which of the following is a potential drawback of database normalization?

Accepted Answer

Increased join operations during queries

Answer

Simplified database structure

Answer

Improved data integrity

Answer

Reduced data redundancy

Question 40

Which of the following is NOT a benefit of database normalization?

Accepted Answer

Increased storage space requirements

Answer

Enhanced data consistency

Answer

Improved data integrity

Answer

Reduced data redundancy

Question 41

A table is in 1NF if it eliminates:

Accepted Answer

Repeating groups

Answer

Partial dependencies

Answer

All functional dependencies

Answer

Transitive dependencies

Question 42

A table is in 2NF if it is in 1NF and eliminates:

Accepted Answer

Partial dependencies

Answer

Transitive dependencies

Answer

Repeating groups

Answer

All functional dependencies

Question 43

A table is in 3NF if it is in 2NF and eliminates:

Accepted Answer

Transitive dependencies

Answer

Partial dependencies

Answer

All functional dependencies

Answer

Repeating groups

Question 44

Consider a table with attributes: StudentID, StudentName, CourseID, CourseName, ProfessorID, ProfessorName. Which of the following represents a partial dependency?

Accepted Answer

StudentName depends on StudentID

Answer

CourseID depends on ProfessorID

Answer

CourseName depends on CourseID

Answer

ProfessorName depends on ProfessorID

Question 45

Consider a table with attributes: CustomerID, CustomerName, OrderID, OrderDate, ProductID, ProductName. Which of the following represents a transitive dependency?

Accepted Answer

OrderDate depends on OrderID, and OrderID depends on CustomerID

Answer

CustomerID depends on CustomerName

Answer

ProductName depends on ProductID

Question 46

You're designing a database for a library. The 'Book' table has these attributes: BookID, Title, Author, Publisher, and ISBN. Which normalization form should you use to ensure data integrity and minimize redundancy?

Accepted Answer

3NF

Answer

BCNF

Answer

1NF

Answer

2NF

Question 47

What is the primary key in a table?

Accepted Answer

A unique identifier for each row in the table.

Answer

An attribute that is not dependent on other attributes.

Answer

An attribute that is not allowed to be null.

Answer

An attribute that is frequently used in queries.

Question 48

What is the main purpose of a foreign key in a relational database?

Accepted Answer

To establish relationships between different tables.

Answer

To enforce data type constraints.

Answer

To uniquely identify rows within a table.

Answer

To ensure data integrity within a single table.

Question 49

Which statement about normalization is TRUE?

Accepted Answer

Normalizing a large database can be a complex and time-consuming process.

Answer

Normalization always produces the optimal database design.

Answer

Normalization is a one-time process that only needs to be done once.

Question 50

What is the primary goal of database normalization?

Accepted Answer

To reduce data redundancy and improve data integrity.

Answer

To increase the complexity of database queries.

Answer

To minimize storage space by completely eliminating data redundancy.

Question 51

Which of these describes a table in First Normal Form (1NF)?

Accepted Answer

Each column contains atomic values, and there are no repeating groups.

Answer

It has a defined primary key, but foreign keys are optional.

Answer

It is free of transitive dependencies between non-key attributes.

Question 52

A table is considered to be in Second Normal Form (2NF) if it's in 1NF and meets which additional condition?

Accepted Answer

All non-key attributes are fully dependent on the entire primary key.

Answer

It has a composite primary key made up of multiple columns.

Answer

There are no relationships with other tables in the database.

Question 53

What type of dependency does Third Normal Form (3NF) aim to eliminate?

Accepted Answer

Transitive dependencies between non-key attributes.

Answer

Foreign key dependencies on tables with overlapping columns.

Answer

Partial dependencies on a part of a composite primary key.

Question 54

What is a potential downside of normalizing a database to higher normal forms?

Accepted Answer

Queries might become more complex due to the need for multiple table joins.

Answer

Higher risk of data anomalies and inconsistencies.

Answer

Reduced data integrity and enforcement of constraints.

Question 55

In a library database, which of these would be considered an 'atom' in the context of 1NF?

Accepted Answer

A single genre tag for a book (e.g., 'Fiction').

Answer

The complete address of a library branch.

Answer

All the books borrowed by a specific member.

Answer

A book's title and author combined in one field.

Question 56

You are designing a database to store orders and customer information. Which scenario would indicate a need for normalization beyond 1NF?

Accepted Answer

Storing multiple product IDs in a single order record.

Answer

Having separate tables for customers and orders.

Answer

Using a unique order ID as the primary key for the order table.

Question 57

How does normalization contribute to maintaining data integrity?

Accepted Answer

By reducing redundant data, updates become consistent across the database.

Answer

Normalization prevents unauthorized access to sensitive data.

Answer

It enforces complex data validation rules at the database level.

Question 58

Which of the following is NOT a benefit typically associated with a well-normalized database?

Accepted Answer

Guaranteed elimination of the need for data cleaning or transformation.

Answer

Improved efficiency in data modification operations (insert, update, delete).

Answer

Reduced storage space required for maintaining the database.

Question 59

When might it be acceptable to denormalize a database design?

Accepted Answer

To improve performance in specific read-heavy operations, despite redundancy.

Answer

When the database is very small and data integrity is not a major concern.

Answer

To simplify the development of complex queries requiring many joins.