WGU C170 Data Management Applications
2025 – 80 Authentic Questions with Schema-
Based Scenarios & 100% Verified Solutions |
A+ Graded
Section 1: Database Concepts and Normalization (Questions
1–20)
1. What is the primary purpose of database normalization?
Minimize data redundancy and ensure data integrity
Rationale: Normalization organizes data to eliminate redundancy and prevent anomalies
during data operations.
2. What is a requirement for a table to be in First Normal Form (1NF)?
No repeating groups and atomic values
Rationale: 1NF requires each column to contain atomic (indivisible) values and no
repeating groups or arrays.
3. What must be true for a table to be in Second Normal Form (2NF)?
In 1NF and no partial dependencies
Rationale: 2NF eliminates partial dependencies, ensuring non-key attributes depend on
the entire primary key.
4. What is required for a table to be in Third Normal Form (3NF)?
In 2NF and no transitive dependencies
Rationale: 3NF removes transitive dependencies, where non-key attributes depend on
other non-key attributes.
5. What is a candidate key?
A minimal superkey that uniquely identifies a tuple
Rationale: A candidate key is a set of attributes that can uniquely identify a record
without redundant attributes.
6. What is a superkey?
A set of attributes that uniquely identifies a tuple
Rationale: A superkey includes any set of attributes that uniquely identifies a record,
including the candidate key and additional attributes.
7. What is a primary key?
A chosen candidate key to uniquely identify records
Rationale: The primary key is selected from candidate keys to enforce uniqueness and
non-null values.
8. What is a foreign key?
A field that references a primary key in another table
, Rationale: Foreign keys establish relationships between tables, ensuring referential
integrity.
9. What does referential integrity ensure?
Foreign key values match primary key values
Rationale: Referential integrity prevents orphaned records by ensuring foreign keys
correspond to valid primary keys.
10. What kind of relationship does a salesperson authorized to sell many products and a
product sold by many salespersons describe?
Many-to-many
Rationale: This scenario requires a junction table to manage the many-to-many
relationship between salespersons and products.
11. What is an associative entity?
Transforms an M:N relationship into two 1:M relationships
Rationale: An associative entity, or bridge table, resolves many-to-many relationships by
including primary keys from both related entities.
12. What is a composite key?
A primary key with multiple attributes
Rationale: A composite key combines two or more attributes to uniquely identify records
in a table.
13. What does a database schema represent?
The structure of a database
Rationale: A schema defines tables, columns, relationships, and constraints in a
database.
14. What is an entity in a database?
An object of interest with attributes
Rationale: Entities represent real-world objects (e.g., Customer, Order) with attributes
stored in tables.
15. What is an attribute in a database?
A property of an entity
Rationale: Attributes are columns in a table that describe characteristics of an entity
(e.g., Customer Name).
16. What is the purpose of an ERD?
Visualize database relationships and structure
Rationale: Entity-Relationship Diagrams (ERDs) depict entities, attributes, and
relationships for conceptual modeling.
17. What does cardinality indicate in an ERD?
Number of instances in a relationship
Rationale: Cardinality specifies how many instances of one entity relate to another (e.g.,
1:M, M:N).
18. What is a transitive dependency?
A non-key attribute depending on another non-key attribute
Rationale: Transitive dependencies are eliminated in 3NF to ensure data integrity.
19. What is a domain in a relational database?
A set of possible values for an attribute
Rationale: A domain defines valid values for a column, such as integers or
TRUE/FALSE.
2025 – 80 Authentic Questions with Schema-
Based Scenarios & 100% Verified Solutions |
A+ Graded
Section 1: Database Concepts and Normalization (Questions
1–20)
1. What is the primary purpose of database normalization?
Minimize data redundancy and ensure data integrity
Rationale: Normalization organizes data to eliminate redundancy and prevent anomalies
during data operations.
2. What is a requirement for a table to be in First Normal Form (1NF)?
No repeating groups and atomic values
Rationale: 1NF requires each column to contain atomic (indivisible) values and no
repeating groups or arrays.
3. What must be true for a table to be in Second Normal Form (2NF)?
In 1NF and no partial dependencies
Rationale: 2NF eliminates partial dependencies, ensuring non-key attributes depend on
the entire primary key.
4. What is required for a table to be in Third Normal Form (3NF)?
In 2NF and no transitive dependencies
Rationale: 3NF removes transitive dependencies, where non-key attributes depend on
other non-key attributes.
5. What is a candidate key?
A minimal superkey that uniquely identifies a tuple
Rationale: A candidate key is a set of attributes that can uniquely identify a record
without redundant attributes.
6. What is a superkey?
A set of attributes that uniquely identifies a tuple
Rationale: A superkey includes any set of attributes that uniquely identifies a record,
including the candidate key and additional attributes.
7. What is a primary key?
A chosen candidate key to uniquely identify records
Rationale: The primary key is selected from candidate keys to enforce uniqueness and
non-null values.
8. What is a foreign key?
A field that references a primary key in another table
, Rationale: Foreign keys establish relationships between tables, ensuring referential
integrity.
9. What does referential integrity ensure?
Foreign key values match primary key values
Rationale: Referential integrity prevents orphaned records by ensuring foreign keys
correspond to valid primary keys.
10. What kind of relationship does a salesperson authorized to sell many products and a
product sold by many salespersons describe?
Many-to-many
Rationale: This scenario requires a junction table to manage the many-to-many
relationship between salespersons and products.
11. What is an associative entity?
Transforms an M:N relationship into two 1:M relationships
Rationale: An associative entity, or bridge table, resolves many-to-many relationships by
including primary keys from both related entities.
12. What is a composite key?
A primary key with multiple attributes
Rationale: A composite key combines two or more attributes to uniquely identify records
in a table.
13. What does a database schema represent?
The structure of a database
Rationale: A schema defines tables, columns, relationships, and constraints in a
database.
14. What is an entity in a database?
An object of interest with attributes
Rationale: Entities represent real-world objects (e.g., Customer, Order) with attributes
stored in tables.
15. What is an attribute in a database?
A property of an entity
Rationale: Attributes are columns in a table that describe characteristics of an entity
(e.g., Customer Name).
16. What is the purpose of an ERD?
Visualize database relationships and structure
Rationale: Entity-Relationship Diagrams (ERDs) depict entities, attributes, and
relationships for conceptual modeling.
17. What does cardinality indicate in an ERD?
Number of instances in a relationship
Rationale: Cardinality specifies how many instances of one entity relate to another (e.g.,
1:M, M:N).
18. What is a transitive dependency?
A non-key attribute depending on another non-key attribute
Rationale: Transitive dependencies are eliminated in 3NF to ensure data integrity.
19. What is a domain in a relational database?
A set of possible values for an attribute
Rationale: A domain defines valid values for a column, such as integers or
TRUE/FALSE.
