D426 DATA MANAGEMENT
FOUNDATIONS - PRACTICE EXAM
QUESTIONS AND ANSWERS
1. Which normal form is achieved when all transitive dependencies are removed?
A. First Normal Form (1NF)
B. Second Normal Form (2NF)
C. Boyce-Codd Normal Form (BCNF)
D. Third Normal Form (3NF)
Answer: D
Conceptual Explanation: Third Normal Form (3NF) requires the table to be in 2NF and
that all non-key attributes are dependent only on the primary key, effectively removing
transitive dependencies.
2. In an Entity-Relationship Diagram (ERD), what does a double diamond symbol represent?
A. Strong relationship
B. Derived attribute
C. Multi-valued attribute
,D. Identifying relationship
Answer: D
Conceptual Explanation: A double diamond represents an identifying relationship, which
connects a weak entity to its owner entity.
3. Which SQL statement is used to remove a table and its data from a database?
A. DELETE TABLE
B. REMOVE TABLE
C. DROP TABLE
D. TRUNCATE TABLE
Answer: C
Conceptual Explanation: DROP TABLE removes the table definition as well as all its data.
DELETE and TRUNCATE only affect the rows within the table.
4. Which relational algebra operation returns a subset of columns from a table?
A. Selection
B. Join
C. Projection
D. Union
Answer: C
, Conceptual Explanation: Projection (pi) extracts specific columns from a relation, while
Selection (sigma) extracts specific rows based on a condition.
5. A composite primary key consists of what?
A. A single attribute that is unique
B. Two or more attributes that together uniquely identify a row
C. A primary key that is also a foreign key
D. A primary key automatically generated by the database system
Answer: B
Conceptual Explanation: A composite key uses multiple columns in combination to
ensure the uniqueness of a record.
6. Which clause in a SELECT statement is used to filter results based on an aggregate
function?
A. WHERE
B. GROUP BY
C. ORDER BY
D. HAVING
Answer: D
Conceptual Explanation: The HAVING clause was added to SQL because the WHERE
keyword could not be used with aggregate functions.
FOUNDATIONS - PRACTICE EXAM
QUESTIONS AND ANSWERS
1. Which normal form is achieved when all transitive dependencies are removed?
A. First Normal Form (1NF)
B. Second Normal Form (2NF)
C. Boyce-Codd Normal Form (BCNF)
D. Third Normal Form (3NF)
Answer: D
Conceptual Explanation: Third Normal Form (3NF) requires the table to be in 2NF and
that all non-key attributes are dependent only on the primary key, effectively removing
transitive dependencies.
2. In an Entity-Relationship Diagram (ERD), what does a double diamond symbol represent?
A. Strong relationship
B. Derived attribute
C. Multi-valued attribute
,D. Identifying relationship
Answer: D
Conceptual Explanation: A double diamond represents an identifying relationship, which
connects a weak entity to its owner entity.
3. Which SQL statement is used to remove a table and its data from a database?
A. DELETE TABLE
B. REMOVE TABLE
C. DROP TABLE
D. TRUNCATE TABLE
Answer: C
Conceptual Explanation: DROP TABLE removes the table definition as well as all its data.
DELETE and TRUNCATE only affect the rows within the table.
4. Which relational algebra operation returns a subset of columns from a table?
A. Selection
B. Join
C. Projection
D. Union
Answer: C
, Conceptual Explanation: Projection (pi) extracts specific columns from a relation, while
Selection (sigma) extracts specific rows based on a condition.
5. A composite primary key consists of what?
A. A single attribute that is unique
B. Two or more attributes that together uniquely identify a row
C. A primary key that is also a foreign key
D. A primary key automatically generated by the database system
Answer: B
Conceptual Explanation: A composite key uses multiple columns in combination to
ensure the uniqueness of a record.
6. Which clause in a SELECT statement is used to filter results based on an aggregate
function?
A. WHERE
B. GROUP BY
C. ORDER BY
D. HAVING
Answer: D
Conceptual Explanation: The HAVING clause was added to SQL because the WHERE
keyword could not be used with aggregate functions.
