WGU D440 Objective Assessment (OA) Practice Exam 2026 U… 2026 Update • Verified Answers
✓ VERIFIED • 2026 UPDATE • 100% ACCURATE
WGU D440 Objective Assessment (OA) Practice
Exam 2026 UPDATE
Actual Exam Questions & Verified Answers
with Detailed Rationales
Document Type: Exam (Elaborations)
Academic Year:
Total Questions: 50 Multiple Choice
Includes: Correct Answers + Full Rationales
Status: Verified & Updated for 2026
Exam (Elaborations) • Actual Questions & Rationales Page 1
,WGU D440 Objective Assessment (OA) Practice Exam 2026 U… 2026 Update • Verified Answers
Questions & Verified Answers
1. Which normal form requires the removal of partial functional dependencies, where an
attribute is dependent on only part of a composite primary key?
A. First Normal Form (1NF)
B. Third Normal Form (3NF)
C. Second Normal Form (2NF)
D. Boyce-Codd Normal Form (BCNF)
Answer: C
Rationale: Second Normal Form (2NF) specifically addresses partial functional dependencies. A table is in
2NF if it is in 1NF and all non-key attributes are fully functional dependent on the entire primary key.
Recognizing this principle allows the nurse to prioritize care, anticipate complications, and provide accurate
patient education.
2. In a SQL query, which clause is used to filter groups created by the GROUP BY clause?
A. WHERE
B. HAVING
C. ORDER BY
D. SELECT
Answer: B
Rationale: The HAVING clause is used to filter groups based on a condition, whereas the WHERE clause is
used to filter individual rows before they are grouped. Exam questions often test the ability to distinguish this
concept from closely related distractors, making a clear rationale essential for mastery. Applying this knowledge
in clinical settings supports safe, evidence-based practice and improves patient outcomes.
3. What is the primary purpose of a Foreign Key in a relational database?
A. To uniquely identify each record in a table.
B. To improve the performance of search queries.
C. To establish and enforce a link between data in two tables.
D. To ensure that a column cannot contain NULL values.
Answer: C
Rationale: A Foreign Key is a field in one table that refers to the Primary Key in another table, establishing a
relationship and maintaining referential integrity between the two. Applying this knowledge in clinical settings
supports safe, evidence-based practice and improves patient outcomes.
Exam (Elaborations) • Actual Questions & Rationales Page 2
, WGU D440 Objective Assessment (OA) Practice Exam 2026 U… 2026 Update • Verified Answers
4. Which SQL statement is used to remove all records from a table without deleting the table
structure itself?
A. DELETE
B. DROP
C. TRUNCATE
D. REMOVE
Answer: C
Rationale: TRUNCATE is a DDL command that removes all rows from a table, but the table structure and its
columns, constraints, and indexes remain intact. DELETE is DML and can be used with a WHERE clause.
Exam questions often test the ability to distinguish this concept from closely related distractors, making a clear
rationale essential for mastery.
5. Which of the following describes a ‘transitive dependency’ in the context of database
normalization?
A. Multiple attributes depend on the same primary key.
B. A non-key attribute depends on a part of the primary key.
C. A primary key depends on a foreign key.
D. A non-key attribute depends on another non-key attribute.
Answer: D
Rationale: Transitive dependency occurs when a non-key attribute is dependent on another non-key attribute.
Removing these dependencies is the requirement for moving from 2NF to 3NF. Applying this knowledge in
clinical settings supports safe, evidence-based practice and improves patient outcomes.
6. In an Entity-Relationship Diagram (ERD), what does a ‘diamond’ symbol typically represent?
A. A Relationship
B. An Attribute
C. An Entity
D. , what does a ‘diamond’ symbol typically represent?
Answer: A
Rationale: In traditional Chen notation for ERDs, rectangles represent entities, ovals represent attributes, and
diamonds represent relationships between entities. Applying this knowledge in clinical settings supports safe,
evidence-based practice and improves patient outcomes. This is an important clinical concept because
selecting the correct answer (A) requires understanding both the pathophysiology and the practical nursing
implications.
Exam (Elaborations) • Actual Questions & Rationales Page 3
✓ VERIFIED • 2026 UPDATE • 100% ACCURATE
WGU D440 Objective Assessment (OA) Practice
Exam 2026 UPDATE
Actual Exam Questions & Verified Answers
with Detailed Rationales
Document Type: Exam (Elaborations)
Academic Year:
Total Questions: 50 Multiple Choice
Includes: Correct Answers + Full Rationales
Status: Verified & Updated for 2026
Exam (Elaborations) • Actual Questions & Rationales Page 1
,WGU D440 Objective Assessment (OA) Practice Exam 2026 U… 2026 Update • Verified Answers
Questions & Verified Answers
1. Which normal form requires the removal of partial functional dependencies, where an
attribute is dependent on only part of a composite primary key?
A. First Normal Form (1NF)
B. Third Normal Form (3NF)
C. Second Normal Form (2NF)
D. Boyce-Codd Normal Form (BCNF)
Answer: C
Rationale: Second Normal Form (2NF) specifically addresses partial functional dependencies. A table is in
2NF if it is in 1NF and all non-key attributes are fully functional dependent on the entire primary key.
Recognizing this principle allows the nurse to prioritize care, anticipate complications, and provide accurate
patient education.
2. In a SQL query, which clause is used to filter groups created by the GROUP BY clause?
A. WHERE
B. HAVING
C. ORDER BY
D. SELECT
Answer: B
Rationale: The HAVING clause is used to filter groups based on a condition, whereas the WHERE clause is
used to filter individual rows before they are grouped. Exam questions often test the ability to distinguish this
concept from closely related distractors, making a clear rationale essential for mastery. Applying this knowledge
in clinical settings supports safe, evidence-based practice and improves patient outcomes.
3. What is the primary purpose of a Foreign Key in a relational database?
A. To uniquely identify each record in a table.
B. To improve the performance of search queries.
C. To establish and enforce a link between data in two tables.
D. To ensure that a column cannot contain NULL values.
Answer: C
Rationale: A Foreign Key is a field in one table that refers to the Primary Key in another table, establishing a
relationship and maintaining referential integrity between the two. Applying this knowledge in clinical settings
supports safe, evidence-based practice and improves patient outcomes.
Exam (Elaborations) • Actual Questions & Rationales Page 2
, WGU D440 Objective Assessment (OA) Practice Exam 2026 U… 2026 Update • Verified Answers
4. Which SQL statement is used to remove all records from a table without deleting the table
structure itself?
A. DELETE
B. DROP
C. TRUNCATE
D. REMOVE
Answer: C
Rationale: TRUNCATE is a DDL command that removes all rows from a table, but the table structure and its
columns, constraints, and indexes remain intact. DELETE is DML and can be used with a WHERE clause.
Exam questions often test the ability to distinguish this concept from closely related distractors, making a clear
rationale essential for mastery.
5. Which of the following describes a ‘transitive dependency’ in the context of database
normalization?
A. Multiple attributes depend on the same primary key.
B. A non-key attribute depends on a part of the primary key.
C. A primary key depends on a foreign key.
D. A non-key attribute depends on another non-key attribute.
Answer: D
Rationale: Transitive dependency occurs when a non-key attribute is dependent on another non-key attribute.
Removing these dependencies is the requirement for moving from 2NF to 3NF. Applying this knowledge in
clinical settings supports safe, evidence-based practice and improves patient outcomes.
6. In an Entity-Relationship Diagram (ERD), what does a ‘diamond’ symbol typically represent?
A. A Relationship
B. An Attribute
C. An Entity
D. , what does a ‘diamond’ symbol typically represent?
Answer: A
Rationale: In traditional Chen notation for ERDs, rectangles represent entities, ovals represent attributes, and
diamonds represent relationships between entities. Applying this knowledge in clinical settings supports safe,
evidence-based practice and improves patient outcomes. This is an important clinical concept because
selecting the correct answer (A) requires understanding both the pathophysiology and the practical nursing
implications.
Exam (Elaborations) • Actual Questions & Rationales Page 3
