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WGU D467 Objective Assessment Final Exam 2025 – Study
Guide, Practice Questions, and Key Concepts
Prepare for the WGU D467 Objective Assessment Final Exam 2025 with this complete study
guide, featuring practice questions, key course concepts, and exam strategies. Perfect for
WGU students looking to pass efficiently and confidently.
Top SEO Keywords (High Search Volume 2025)
• WGU D467 Objective Assessment
• WGU D467 Final Exam 2025
• WGU D467 study guide
• WGU D467 practice questions
How can referential integrity violations be corrected? - ANSWER-
Violations can be corrected manually or automatically using SQL
constraints such as RESTRICT, SET NULL, SET DEFAULT, or
CASCADE.
What does the RESTRICT constraint do in SQL? - ANSWER-The
RESTRICT constraint rejects any insert, update, or delete
operation that violates referential integrity.
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What does the SET NULL constraint do in SQL? - ANSWER-The
SET NULL constraint sets invalid foreign keys to NULL when the
referenced primary key is deleted or updated.
What does the SET DEFAULT constraint do in SQL? - ANSWER-
The SET DEFAULT constraint sets invalid foreign keys to their
default value when the referenced primary key is deleted or
updated.
Which table has a composite foreign key? ```plaintext 1.
DepartmentStaff table 2. EmployeeManager table 3. HealthPlan
table ``` - ANSWER-HealthPlan table
What is referential integrity in relational databases? - ANSWER-
Referential integrity is a rule that requires foreign key values to be
either fully NULL or match some primary key value.
What are the four ways to violate referential integrity? - ANSWER-
1. A primary key is updated. 2. A foreign key is updated. 3. A row
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containing a primary key is deleted. 4. A row containing a foreign
key is inserted.
Refer to the Department and Employee tables. Identify the foreign
key value that violates referential integrity. ```plaintext Department
Code Name Manager 44 Engineering 2538 82 Sales 6381 12
Marketing 6381 99 Technical Support 3829 Employee ID Name
Salary 2538 Lisa Ellison 45000 5384 Sam Snead 30500 6381
Maria Rodriguez 92300 ``` - ANSWER-Manager 3829 in the
Technical Support department violates referential integrity
because there is no employee with ID 3829.
What does the CASCADE constraint do in SQL? - ANSWER-The
CASCADE constraint propagates primary key changes to foreign
keys. If a primary key is deleted, matching foreign keys are also
deleted. If a primary key is updated, matching foreign keys are
updated to the new value.
What do the ON DELETE and ON UPDATE clauses specify in a
FOREIGN KEY constraint? - ANSWER-The ON DELETE and ON
UPDATE clauses specify the actions to be taken when the
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referenced primary key is deleted or updated. Options include
RESTRICT, SET NULL, SET DEFAULT, and CASCADE.
Refer to the following CREATE TABLE statement. What actions
are specified for ON DELETE and ON UPDATE? ```sql CREATE
TABLE Department ( Code TINYINT UNSIGNED, Name
VARCHAR(20), ManagerID SMALLINT UNSIGNED, PRIMARY
KEY (Code), FOREIGN KEY (ManagerID) REFERENCES
Employee(ID) ON DELETE SET NULL ON UPDATE CASCADE );
``` - ANSWER-- ON DELETE SET NULL: When the referenced
primary key is deleted, the foreign key is set to NULL. - ON
UPDATE CASCADE: When the referenced primary key is
updated, the foreign key is updated to the new value.
True or False: A fully NULL foreign key violates referential
integrity. - ANSWER-False
What happens if Maria Rodriguez's ID is changed to 9925 in the
Employee table? ```plaintext Employee ID Name Salary 2538 Lisa
Ellison 45000 5384 Sam Snead 30500 6381 Maria Rodriguez
92300 Department Code Name Manager 44 Engineering 2538 82
Sales 6381 12 Marketing 6381 99 Technical Support NULL ``` -
WGU D467 Objective Assessment Final Exam 2025 – Study
Guide, Practice Questions, and Key Concepts
Prepare for the WGU D467 Objective Assessment Final Exam 2025 with this complete study
guide, featuring practice questions, key course concepts, and exam strategies. Perfect for
WGU students looking to pass efficiently and confidently.
Top SEO Keywords (High Search Volume 2025)
• WGU D467 Objective Assessment
• WGU D467 Final Exam 2025
• WGU D467 study guide
• WGU D467 practice questions
How can referential integrity violations be corrected? - ANSWER-
Violations can be corrected manually or automatically using SQL
constraints such as RESTRICT, SET NULL, SET DEFAULT, or
CASCADE.
What does the RESTRICT constraint do in SQL? - ANSWER-The
RESTRICT constraint rejects any insert, update, or delete
operation that violates referential integrity.
,2|Page
What does the SET NULL constraint do in SQL? - ANSWER-The
SET NULL constraint sets invalid foreign keys to NULL when the
referenced primary key is deleted or updated.
What does the SET DEFAULT constraint do in SQL? - ANSWER-
The SET DEFAULT constraint sets invalid foreign keys to their
default value when the referenced primary key is deleted or
updated.
Which table has a composite foreign key? ```plaintext 1.
DepartmentStaff table 2. EmployeeManager table 3. HealthPlan
table ``` - ANSWER-HealthPlan table
What is referential integrity in relational databases? - ANSWER-
Referential integrity is a rule that requires foreign key values to be
either fully NULL or match some primary key value.
What are the four ways to violate referential integrity? - ANSWER-
1. A primary key is updated. 2. A foreign key is updated. 3. A row
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containing a primary key is deleted. 4. A row containing a foreign
key is inserted.
Refer to the Department and Employee tables. Identify the foreign
key value that violates referential integrity. ```plaintext Department
Code Name Manager 44 Engineering 2538 82 Sales 6381 12
Marketing 6381 99 Technical Support 3829 Employee ID Name
Salary 2538 Lisa Ellison 45000 5384 Sam Snead 30500 6381
Maria Rodriguez 92300 ``` - ANSWER-Manager 3829 in the
Technical Support department violates referential integrity
because there is no employee with ID 3829.
What does the CASCADE constraint do in SQL? - ANSWER-The
CASCADE constraint propagates primary key changes to foreign
keys. If a primary key is deleted, matching foreign keys are also
deleted. If a primary key is updated, matching foreign keys are
updated to the new value.
What do the ON DELETE and ON UPDATE clauses specify in a
FOREIGN KEY constraint? - ANSWER-The ON DELETE and ON
UPDATE clauses specify the actions to be taken when the
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referenced primary key is deleted or updated. Options include
RESTRICT, SET NULL, SET DEFAULT, and CASCADE.
Refer to the following CREATE TABLE statement. What actions
are specified for ON DELETE and ON UPDATE? ```sql CREATE
TABLE Department ( Code TINYINT UNSIGNED, Name
VARCHAR(20), ManagerID SMALLINT UNSIGNED, PRIMARY
KEY (Code), FOREIGN KEY (ManagerID) REFERENCES
Employee(ID) ON DELETE SET NULL ON UPDATE CASCADE );
``` - ANSWER-- ON DELETE SET NULL: When the referenced
primary key is deleted, the foreign key is set to NULL. - ON
UPDATE CASCADE: When the referenced primary key is
updated, the foreign key is updated to the new value.
True or False: A fully NULL foreign key violates referential
integrity. - ANSWER-False
What happens if Maria Rodriguez's ID is changed to 9925 in the
Employee table? ```plaintext Employee ID Name Salary 2538 Lisa
Ellison 45000 5384 Sam Snead 30500 6381 Maria Rodriguez
92300 Department Code Name Manager 44 Engineering 2538 82
Sales 6381 12 Marketing 6381 99 Technical Support NULL ``` -
