D 427 / D427 Pre - Assessment V1 (Latest
Update ) Data Management –
Applications | Questions and Answers |
Grade A | 100% Correct (Verified
Answers) - WGU
Database Fundamentals
1. What does the acronym CRUD stand for in database management?
Answer: Create, Read, Update, Delete
Rationale: CRUD represents the four basic operations for managing data in a database
system.
2. What is a database model?
Answer: A conceptual framework for organizing data, including data structures,
operations, and constraints
Rationale: A database model defines how data is stored, accessed, and managed.
3. What is a relational database?
Answer: A database that organizes data into tables with relationships defined by keys
Rationale: Relational databases use tables, columns, and rows with primary and foreign
keys to establish relationships.
4. What is a primary key?
Answer: A unique identifier for each row in a table
Rationale: Primary keys ensure each record is unique and can be referenced by other
tables.
,5. What is a foreign key?
Answer: A column in one table that refers to the primary key in another table
Rationale: Foreign keys enforce referential integrity between related tables.
6. What is a table in a database?
Answer: A collection of rows and columns storing data
Rationale: Tables are the core structure for organizing data in a relational database.
7. What is a row in a database table?
Answer: An unnamed tuple of values corresponding to columns
Rationale: Each row represents a single record in a table.
8. What is a column in a database table?
Answer: A named attribute with a specific data type
Rationale: Columns define the structure and data type of the table’s attributes.
9. What is a data type?
Answer: A named set of values from which column values are drawn
Rationale: Data types (e.g., INT, VARCHAR) specify the kind of data a column can
hold.
10. What is the purpose of relational algebra?
Answer: To provide a theoretical foundation for SQL operations
Rationale: Relational algebra defines operations like selection and projection used in
SQL queries.
11. What is a tuple in a database?
Answer: An ordered collection of elements enclosed in parentheses
Rationale: In relational databases, a tuple corresponds to a row in a table.
, 12. What is a set in a database context?
Answer: An unordered collection of elements enclosed in braces
Rationale: Sets are used to describe collections of rows or values in relational databases.
13. What is a materialized view?
Answer: A stored query result that must be refreshed when the base table changes
Rationale: Materialized views store data physically and require periodic updates.
14. Which two statements are true about a materialized view?
Answer: It is stored; It must be refreshed whenever the base table changes
Rationale: Materialized views are physically stored and need refreshing to reflect base
table updates.
15. What is the purpose of a schema in a database?
Answer: To define the structure and organization of the database
Rationale: A schema specifies tables, columns, data types, and relationships.
16. What is a database management system (DBMS)?
Answer: Software for creating, managing, and querying databases
Rationale: DBMS (e.g., MySQL) facilitates data storage, retrieval, and manipulation.
17. What is the DATE data type syntax?
Answer: YYYY-MM-DD
Rationale: The DATE data type stores dates in a standardized format.
18. What is the DATETIME data type syntax?
Answer: YYYY-MM-DD HH:MM:SS
Rationale: DATETIME includes both date and time components.
19. What does DECIMAL(3,2) indicate?
Answer: Three digits total, two after the decimal point
Rationale: DECIMAL specifies precision and scale for numeric values.
Update ) Data Management –
Applications | Questions and Answers |
Grade A | 100% Correct (Verified
Answers) - WGU
Database Fundamentals
1. What does the acronym CRUD stand for in database management?
Answer: Create, Read, Update, Delete
Rationale: CRUD represents the four basic operations for managing data in a database
system.
2. What is a database model?
Answer: A conceptual framework for organizing data, including data structures,
operations, and constraints
Rationale: A database model defines how data is stored, accessed, and managed.
3. What is a relational database?
Answer: A database that organizes data into tables with relationships defined by keys
Rationale: Relational databases use tables, columns, and rows with primary and foreign
keys to establish relationships.
4. What is a primary key?
Answer: A unique identifier for each row in a table
Rationale: Primary keys ensure each record is unique and can be referenced by other
tables.
,5. What is a foreign key?
Answer: A column in one table that refers to the primary key in another table
Rationale: Foreign keys enforce referential integrity between related tables.
6. What is a table in a database?
Answer: A collection of rows and columns storing data
Rationale: Tables are the core structure for organizing data in a relational database.
7. What is a row in a database table?
Answer: An unnamed tuple of values corresponding to columns
Rationale: Each row represents a single record in a table.
8. What is a column in a database table?
Answer: A named attribute with a specific data type
Rationale: Columns define the structure and data type of the table’s attributes.
9. What is a data type?
Answer: A named set of values from which column values are drawn
Rationale: Data types (e.g., INT, VARCHAR) specify the kind of data a column can
hold.
10. What is the purpose of relational algebra?
Answer: To provide a theoretical foundation for SQL operations
Rationale: Relational algebra defines operations like selection and projection used in
SQL queries.
11. What is a tuple in a database?
Answer: An ordered collection of elements enclosed in parentheses
Rationale: In relational databases, a tuple corresponds to a row in a table.
, 12. What is a set in a database context?
Answer: An unordered collection of elements enclosed in braces
Rationale: Sets are used to describe collections of rows or values in relational databases.
13. What is a materialized view?
Answer: A stored query result that must be refreshed when the base table changes
Rationale: Materialized views store data physically and require periodic updates.
14. Which two statements are true about a materialized view?
Answer: It is stored; It must be refreshed whenever the base table changes
Rationale: Materialized views are physically stored and need refreshing to reflect base
table updates.
15. What is the purpose of a schema in a database?
Answer: To define the structure and organization of the database
Rationale: A schema specifies tables, columns, data types, and relationships.
16. What is a database management system (DBMS)?
Answer: Software for creating, managing, and querying databases
Rationale: DBMS (e.g., MySQL) facilitates data storage, retrieval, and manipulation.
17. What is the DATE data type syntax?
Answer: YYYY-MM-DD
Rationale: The DATE data type stores dates in a standardized format.
18. What is the DATETIME data type syntax?
Answer: YYYY-MM-DD HH:MM:SS
Rationale: DATETIME includes both date and time components.
19. What does DECIMAL(3,2) indicate?
Answer: Three digits total, two after the decimal point
Rationale: DECIMAL specifies precision and scale for numeric values.
