lOMoAR cPSD| 62301842
WGU D426 OA FINAL EXAM REFERENTIAL INTEGRITY AND
DATA MODEL VERIFIED STUDY QUESTIONS AND ANSWERS
2026 UPDATES
C
1. What does modality refer to? How does it appear on a ER diagram?
a. Refers to the MINIUMUM number of times an instance in one entity can be
associated with instance of another entity(minima). Appears as a 0 or 1 on the
relationship line, next to cardinality.
2. Define: Referential Integrity
a. Requires that ALL foreign key values must either be fully NULL or match some
primary key.
3. Four ways Referential Integrity can be violated:
a. Primary key is updated
b. Foreign key is updated
c. Row containing primary key is deleted
d. Row containing foreign key is inserted
4. Actions to Correct Referential Integrity Violation:
a. RESTRICT – rejects an insert, update or delete
b. SET NULL – sets invalid foreign keys to null
c. SET DEFAULT – sets invalid foreign keys to a default primary value
d. CASCADE – propagates primary key changes to foreign keys 5. What is an
important aspect to referential integrity?
a. Reference to data in one relation is based on values in another relation.
6. What is a broad definition of data?
a. Raw facts captured or printed on digital media.
7. What are data?
a. Facts that are collection and stored in a database system.
8. What is a determining characteristic of unstructured data?
a. It does not follow a data model.
9. What is true about flat files?
WGU D426 OA FINAL EXAM REFERENTIAL INTEGRITY AND
DATA MODEL VERIFIED STUDY QUESTIONS AND ANSWERS
2026 UPDATES
C
1. What does modality refer to? How does it appear on a ER diagram?
a. Refers to the MINIUMUM number of times an instance in one entity can be
associated with instance of another entity(minima). Appears as a 0 or 1 on the
relationship line, next to cardinality.
2. Define: Referential Integrity
a. Requires that ALL foreign key values must either be fully NULL or match some
primary key.
3. Four ways Referential Integrity can be violated:
a. Primary key is updated
b. Foreign key is updated
c. Row containing primary key is deleted
d. Row containing foreign key is inserted
4. Actions to Correct Referential Integrity Violation:
a. RESTRICT – rejects an insert, update or delete
b. SET NULL – sets invalid foreign keys to null
c. SET DEFAULT – sets invalid foreign keys to a default primary value
d. CASCADE – propagates primary key changes to foreign keys 5. What is an
important aspect to referential integrity?
a. Reference to data in one relation is based on values in another relation.
6. What is a broad definition of data?
a. Raw facts captured or printed on digital media.
7. What are data?
a. Facts that are collection and stored in a database system.
8. What is a determining characteristic of unstructured data?
a. It does not follow a data model.
9. What is true about flat files?
