WGU D426 V3 DATA MANAGEMENT
FOUNDATIONS OA MASTER STUDY
GUIDE
1. Which of the following describes the ‘atomicity’ requirement of the First Normal Form
(1NF)?
A. Each column must contain only one value from the type domain.
B. Every non-key attribute must be fully functionally dependent on the primary key.
C. There must be no transitive dependencies between non-key attributes.
D. The table must have a composite primary key to ensure uniqueness.
Answer: A
Conceptual Explanation: 1NF requires that all attributes contain atomic values, meaning a
single value from the domain of that column, and no repeating groups or arrays.
2. In a relational database, what is a ‘superkey’?
A. A candidate key that has been selected to identify rows uniquely.
B. Any set of one or more columns that, taken collectively, allows us to identify uniquely a
row in a table.
,C. A foreign key that references a primary key in the same table.
D. A key that contains only the minimum number of attributes necessary to ensure
uniqueness.
Answer: B
Conceptual Explanation: A superkey is any set of attributes that uniquely identifies a
tuple. A candidate key is a ‘minimal’ superkey.
3. Which relational algebra operation is represented by the Greek letter sigma (σ)?
A. Projection
B. Selection
C. Join
D. Union
Answer: B
Conceptual Explanation: The selection operator (σ) filters rows based on a specific
condition, returning a subset of the original tuples.
4. A table is in Second Normal Form (2NF) if it is in 1NF and what other condition is met?
A. It contains no transitive dependencies.
B. Every non-prime attribute is fully functionally dependent on every candidate key.
C. All determinants are candidate keys.
, D. It contains no multi-valued attributes.
Answer: B
Conceptual Explanation: 2NF requires that there are no partial functional dependencies;
every non-key attribute must depend on the whole primary key, not just a part of it.
5. Which SQL statement is used to remove all records from a table without deleting the table
structure itself?
A. DROP TABLE
B. TRUNCATE TABLE
C. REMOVE TABLE
D. DELETE SCHEMA
Answer: B
Conceptual Explanation: TRUNCATE TABLE removes all rows from a table, but the table
structure and its columns, constraints, and indexes remain intact.
6. What is the primary difference between a ‘WHERE’ clause and a ‘HAVING’ clause in SQL?
A. HAVING filters rows before grouping, while WHERE filters groups.
B. WHERE filters rows before grouping, while HAVING filters groups after the GROUP BY
clause.
C. WHERE is used for numeric data, while HAVING is used for string data.
D. There is no difference; they are interchangeable.
FOUNDATIONS OA MASTER STUDY
GUIDE
1. Which of the following describes the ‘atomicity’ requirement of the First Normal Form
(1NF)?
A. Each column must contain only one value from the type domain.
B. Every non-key attribute must be fully functionally dependent on the primary key.
C. There must be no transitive dependencies between non-key attributes.
D. The table must have a composite primary key to ensure uniqueness.
Answer: A
Conceptual Explanation: 1NF requires that all attributes contain atomic values, meaning a
single value from the domain of that column, and no repeating groups or arrays.
2. In a relational database, what is a ‘superkey’?
A. A candidate key that has been selected to identify rows uniquely.
B. Any set of one or more columns that, taken collectively, allows us to identify uniquely a
row in a table.
,C. A foreign key that references a primary key in the same table.
D. A key that contains only the minimum number of attributes necessary to ensure
uniqueness.
Answer: B
Conceptual Explanation: A superkey is any set of attributes that uniquely identifies a
tuple. A candidate key is a ‘minimal’ superkey.
3. Which relational algebra operation is represented by the Greek letter sigma (σ)?
A. Projection
B. Selection
C. Join
D. Union
Answer: B
Conceptual Explanation: The selection operator (σ) filters rows based on a specific
condition, returning a subset of the original tuples.
4. A table is in Second Normal Form (2NF) if it is in 1NF and what other condition is met?
A. It contains no transitive dependencies.
B. Every non-prime attribute is fully functionally dependent on every candidate key.
C. All determinants are candidate keys.
, D. It contains no multi-valued attributes.
Answer: B
Conceptual Explanation: 2NF requires that there are no partial functional dependencies;
every non-key attribute must depend on the whole primary key, not just a part of it.
5. Which SQL statement is used to remove all records from a table without deleting the table
structure itself?
A. DROP TABLE
B. TRUNCATE TABLE
C. REMOVE TABLE
D. DELETE SCHEMA
Answer: B
Conceptual Explanation: TRUNCATE TABLE removes all rows from a table, but the table
structure and its columns, constraints, and indexes remain intact.
6. What is the primary difference between a ‘WHERE’ clause and a ‘HAVING’ clause in SQL?
A. HAVING filters rows before grouping, while WHERE filters groups.
B. WHERE filters rows before grouping, while HAVING filters groups after the GROUP BY
clause.
C. WHERE is used for numeric data, while HAVING is used for string data.
D. There is no difference; they are interchangeable.
