WGU D426 DATA MANAGEMENT
FOUNDATIONS FINAL EXAM PREP
QUESTIONS AND ANSWERS
1. Which of the following describes a relation in the context of the relational model?
A. A set of columns and rows that are ordered by their physical storage location.
B. A mathematical set of tuples where the order of rows and columns is irrelevant.
C. A specific instance of an entity within a database.
D. A collection of related tables containing metadata.
Answer: B
Conceptual Explanation: In the relational model, a relation is defined as a set of tuples.
Since it is a set, the ordering of elements does not matter.
2. What is the primary difference between a candidate key and a primary key?
A. A candidate key can contain null values, whereas a primary key cannot.
B. A candidate key is a foreign key in another table.
C. A candidate key must be a composite key, while a primary key is always a single
attribute.
D. A primary key is the specific candidate key selected to uniquely identify rows in a table.
,Answer: D
Conceptual Explanation: Multiple candidate keys can exist for a table; the primary key is
the one chosen by the DBA to serve as the unique identifier.
3. A table is in First Normal Form (1NF) if which condition is met?
A. All non-key attributes are dependent on the whole primary key.
B. The table is linked to another table via a foreign key.
C. There are no transitive dependencies between non-key attributes.
D. Every attribute contains only atomic values and there are no repeating groups.
Answer: D
Conceptual Explanation: 1NF requires that all column values be atomic (indivisible) and
that the table has no repeating groups or multi-valued attributes.
4. Which normal form is specifically violated if a non-key attribute depends on only a portion
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
, Conceptual Explanation: Second Normal Form (2NF) requires that the table is in 1NF and
that no partial functional dependencies exist; non-key attributes must depend on the entire
primary key.
5. What is a transitive dependency in the context of database normalization?
A. When a non-key attribute depends on another non-key attribute.
B. When a primary key depends on a foreign key.
C. When a composite key is split into multiple tables.
D. When an attribute depends on a part of the primary key.
Answer: A
Conceptual Explanation: Transitive dependency occurs when a non-key attribute is
functionally dependent on another non-key attribute, which is a violation of 3NF.
6. In relational algebra, which operator is used to filter rows based on a specific condition?
A. Projection (Pi)
B. Join (Bowtie)
C. Selection (Sigma)
D. Union (U)
Answer: C
Conceptual Explanation: Selection (symbolized by Sigma) is used to retrieve a subset of
rows that meet a given predicate, similar to the SQL WHERE clause.
FOUNDATIONS FINAL EXAM PREP
QUESTIONS AND ANSWERS
1. Which of the following describes a relation in the context of the relational model?
A. A set of columns and rows that are ordered by their physical storage location.
B. A mathematical set of tuples where the order of rows and columns is irrelevant.
C. A specific instance of an entity within a database.
D. A collection of related tables containing metadata.
Answer: B
Conceptual Explanation: In the relational model, a relation is defined as a set of tuples.
Since it is a set, the ordering of elements does not matter.
2. What is the primary difference between a candidate key and a primary key?
A. A candidate key can contain null values, whereas a primary key cannot.
B. A candidate key is a foreign key in another table.
C. A candidate key must be a composite key, while a primary key is always a single
attribute.
D. A primary key is the specific candidate key selected to uniquely identify rows in a table.
,Answer: D
Conceptual Explanation: Multiple candidate keys can exist for a table; the primary key is
the one chosen by the DBA to serve as the unique identifier.
3. A table is in First Normal Form (1NF) if which condition is met?
A. All non-key attributes are dependent on the whole primary key.
B. The table is linked to another table via a foreign key.
C. There are no transitive dependencies between non-key attributes.
D. Every attribute contains only atomic values and there are no repeating groups.
Answer: D
Conceptual Explanation: 1NF requires that all column values be atomic (indivisible) and
that the table has no repeating groups or multi-valued attributes.
4. Which normal form is specifically violated if a non-key attribute depends on only a portion
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
, Conceptual Explanation: Second Normal Form (2NF) requires that the table is in 1NF and
that no partial functional dependencies exist; non-key attributes must depend on the entire
primary key.
5. What is a transitive dependency in the context of database normalization?
A. When a non-key attribute depends on another non-key attribute.
B. When a primary key depends on a foreign key.
C. When a composite key is split into multiple tables.
D. When an attribute depends on a part of the primary key.
Answer: A
Conceptual Explanation: Transitive dependency occurs when a non-key attribute is
functionally dependent on another non-key attribute, which is a violation of 3NF.
6. In relational algebra, which operator is used to filter rows based on a specific condition?
A. Projection (Pi)
B. Join (Bowtie)
C. Selection (Sigma)
D. Union (U)
Answer: C
Conceptual Explanation: Selection (symbolized by Sigma) is used to retrieve a subset of
rows that meet a given predicate, similar to the SQL WHERE clause.