WGU C175/D426 DATA MANAGEMENT
FOUNDATIONS EXAM STUDY GUIDE 2025 – 300
Accurate Questions with Correct Detailed
Answers & Rationales || OA Exam || Verified
---
**1. What is the primary purpose of a database?**
A) To create spreadsheets for financial data.
B) To provide an organized structure for storing, retrieving, and managing data.
C) To replace all file-based data storage systems.
D) To serve as a backup for application source code.
**Answer: B) To provide an organized structure for storing, retrieving, and managing data.**
**Rationale:** This is the fundamental definition of a database. While databases can reduce
the need for file-based systems (C), they don't replace them entirely. Their main purpose is not
spreadsheets (A) or code backup (D), but efficient data management.
**2. Which of the following is a disadvantage of traditional file-processing systems compared to
database systems?**
A) Reduced data redundancy.
B) Improved data integrity.
C) Program-data dependence.
D) Easier data access.
**Answer: C) Program-data dependence.**
,**Rationale:** In file-processing systems, the structure of data files is defined within the
application programs, leading to program-data dependence. This makes it difficult to change
data structures without modifying all programs that use that data. Databases are designed to
minimize this. Options A, B, and D are all *advantages* of database systems.
**3. The three-schema architecture of a database system aims to achieve which of the
following?**
A) Data Independence
B) Data Redundancy
C) Data Dependence
D) Data Processing
**Answer: A) Data Independence**
**Rationale:** The three-schema architecture (internal, conceptual, external) separates the
physical storage of data from how users view it. This separation allows changes to the physical
storage (internal schema) without affecting the application's view of the data (external schema),
and vice versa, which is the definition of data independence.
**4. In the relational model, a relation corresponds to which of the following?**
A) A File
B) A Field
C) A Record
D) A Table
**Answer: D) A Table**
**Rationale:** In the relational model, the core structure is the relation, which is visually
represented as a table with rows and columns. A file (A) is a physical storage concept, a field (B)
is a column/attribute, and a record (C) is a row/tuple.
, **5. What is a tuple in a relational database?**
A) A column in a table.
B) A set of allowable values for a column.
C) A row in a table.
D) A definition of a table's structure.
**Answer: C) A row in a table.**
**Rationale:** A tuple is the formal term for a row in a relational table. A column is an attribute
(A). A set of allowable values is a domain (B). The table structure is defined by its schema (D).
**6. Which term describes a set of allowable values for an attribute in a relation?**
A) Tuple
B) Domain
C) Schema
D) Key
**Answer: B) Domain**
**Rationale:** A domain defines the possible set of values that an attribute can hold (e.g.,
INTEGER, VARCHAR(50), a specific list of codes). A tuple (A) is a row. A schema (C) is the
structure. A key (D) is a constraint for uniqueness.
**7. A primary key must be which of the following?**
A) Null and Unique
B) Not Null and Unique
C) Null and Not Unique
D) Not Null, but can be Non-Unique
FOUNDATIONS EXAM STUDY GUIDE 2025 – 300
Accurate Questions with Correct Detailed
Answers & Rationales || OA Exam || Verified
---
**1. What is the primary purpose of a database?**
A) To create spreadsheets for financial data.
B) To provide an organized structure for storing, retrieving, and managing data.
C) To replace all file-based data storage systems.
D) To serve as a backup for application source code.
**Answer: B) To provide an organized structure for storing, retrieving, and managing data.**
**Rationale:** This is the fundamental definition of a database. While databases can reduce
the need for file-based systems (C), they don't replace them entirely. Their main purpose is not
spreadsheets (A) or code backup (D), but efficient data management.
**2. Which of the following is a disadvantage of traditional file-processing systems compared to
database systems?**
A) Reduced data redundancy.
B) Improved data integrity.
C) Program-data dependence.
D) Easier data access.
**Answer: C) Program-data dependence.**
,**Rationale:** In file-processing systems, the structure of data files is defined within the
application programs, leading to program-data dependence. This makes it difficult to change
data structures without modifying all programs that use that data. Databases are designed to
minimize this. Options A, B, and D are all *advantages* of database systems.
**3. The three-schema architecture of a database system aims to achieve which of the
following?**
A) Data Independence
B) Data Redundancy
C) Data Dependence
D) Data Processing
**Answer: A) Data Independence**
**Rationale:** The three-schema architecture (internal, conceptual, external) separates the
physical storage of data from how users view it. This separation allows changes to the physical
storage (internal schema) without affecting the application's view of the data (external schema),
and vice versa, which is the definition of data independence.
**4. In the relational model, a relation corresponds to which of the following?**
A) A File
B) A Field
C) A Record
D) A Table
**Answer: D) A Table**
**Rationale:** In the relational model, the core structure is the relation, which is visually
represented as a table with rows and columns. A file (A) is a physical storage concept, a field (B)
is a column/attribute, and a record (C) is a row/tuple.
, **5. What is a tuple in a relational database?**
A) A column in a table.
B) A set of allowable values for a column.
C) A row in a table.
D) A definition of a table's structure.
**Answer: C) A row in a table.**
**Rationale:** A tuple is the formal term for a row in a relational table. A column is an attribute
(A). A set of allowable values is a domain (B). The table structure is defined by its schema (D).
**6. Which term describes a set of allowable values for an attribute in a relation?**
A) Tuple
B) Domain
C) Schema
D) Key
**Answer: B) Domain**
**Rationale:** A domain defines the possible set of values that an attribute can hold (e.g.,
INTEGER, VARCHAR(50), a specific list of codes). A tuple (A) is a row. A schema (C) is the
structure. A key (D) is a constraint for uniqueness.
**7. A primary key must be which of the following?**
A) Null and Unique
B) Not Null and Unique
C) Null and Not Unique
D) Not Null, but can be Non-Unique
