WGU D326 – Advanced Data
Management Final Prep Exam (Latest
Update 2026/2027) Questions and
Verified Answers | 100% Correct |
Grade A.
1. Which database design principle ensures that each table contains
information about only one subject and reduces data redundancy?
A. Denormalization
B. Indexing
C. Normalization
D. Partitioning
Rationale: Normalization is the process of organizing data into related
tables to reduce redundancy, improve data integrity, and prevent
update anomalies. It typically involves applying normal forms such as
1NF, 2NF, and 3NF.
2. A database administrator wants to ensure that every value in a
primary key column is unique and never null. Which database
constraint provides this guarantee?
,A. Foreign key constraint
B. Check constraint
C. Primary key constraint
D. Default constraint
Rationale: A primary key constraint uniquely identifies each record in a
table and automatically enforces both uniqueness and non-null
requirements.
3. Which SQL statement is used to remove an entire table definition
and its associated data from a database?
A. DELETE
B. REMOVE
C. CLEAR
D. DROP TABLE
Rationale: DROP TABLE permanently removes the table structure and all
data contained within it. DELETE removes rows but leaves the table
structure intact.
4. What is the primary purpose of creating an index on a database
column?
A. Increase data storage capacity
B. Improve query performance
C. Eliminate the need for backups
D. Prevent unauthorized access
,Rationale: Indexes improve query performance by creating a faster
lookup structure for retrieving rows. However, excessive indexing can
increase storage requirements and slow write operations.
5. Which type of database relationship exists when one record in a
table can be associated with many records in another table?
A. One-to-one
B. One-to-many
C. Many-to-one only
D. Many-to-many only
Rationale: A one-to-many relationship occurs when a single record in
one table relates to multiple records in another table. For example, one
customer can place many orders.
6. Which ACID property ensures that a transaction is completed
entirely or not at all?
A. Consistency
B. Isolation
C. Atomicity
D. Durability
Rationale: Atomicity guarantees that a transaction is treated as a single
unit. If any part of the transaction fails, the entire transaction is rolled
back.
7. In a relational database, what is the purpose of a foreign key?
, A. Encrypt sensitive information
B. Create database backups
C. Establish relationships between tables
D. Improve hardware performance
Rationale: A foreign key references a primary key in another table and
establishes a relationship between the two tables while maintaining
referential integrity.
8. Which SQL command is used to modify existing records in a table?
A. INSERT
B. UPDATE
C. ALTER
D. MODIFY
Rationale: The UPDATE statement changes existing rows in a table.
INSERT adds new records, while ALTER changes the structure of
database objects.
9. What is the main purpose of a database transaction?
A. Compress database files
B. Create user accounts
C. Execute a group of operations as a single logical unit
D. Remove duplicate tables
Rationale: Transactions group multiple database operations together so
they can succeed or fail as one unit, preserving data integrity.
Management Final Prep Exam (Latest
Update 2026/2027) Questions and
Verified Answers | 100% Correct |
Grade A.
1. Which database design principle ensures that each table contains
information about only one subject and reduces data redundancy?
A. Denormalization
B. Indexing
C. Normalization
D. Partitioning
Rationale: Normalization is the process of organizing data into related
tables to reduce redundancy, improve data integrity, and prevent
update anomalies. It typically involves applying normal forms such as
1NF, 2NF, and 3NF.
2. A database administrator wants to ensure that every value in a
primary key column is unique and never null. Which database
constraint provides this guarantee?
,A. Foreign key constraint
B. Check constraint
C. Primary key constraint
D. Default constraint
Rationale: A primary key constraint uniquely identifies each record in a
table and automatically enforces both uniqueness and non-null
requirements.
3. Which SQL statement is used to remove an entire table definition
and its associated data from a database?
A. DELETE
B. REMOVE
C. CLEAR
D. DROP TABLE
Rationale: DROP TABLE permanently removes the table structure and all
data contained within it. DELETE removes rows but leaves the table
structure intact.
4. What is the primary purpose of creating an index on a database
column?
A. Increase data storage capacity
B. Improve query performance
C. Eliminate the need for backups
D. Prevent unauthorized access
,Rationale: Indexes improve query performance by creating a faster
lookup structure for retrieving rows. However, excessive indexing can
increase storage requirements and slow write operations.
5. Which type of database relationship exists when one record in a
table can be associated with many records in another table?
A. One-to-one
B. One-to-many
C. Many-to-one only
D. Many-to-many only
Rationale: A one-to-many relationship occurs when a single record in
one table relates to multiple records in another table. For example, one
customer can place many orders.
6. Which ACID property ensures that a transaction is completed
entirely or not at all?
A. Consistency
B. Isolation
C. Atomicity
D. Durability
Rationale: Atomicity guarantees that a transaction is treated as a single
unit. If any part of the transaction fails, the entire transaction is rolled
back.
7. In a relational database, what is the purpose of a foreign key?
, A. Encrypt sensitive information
B. Create database backups
C. Establish relationships between tables
D. Improve hardware performance
Rationale: A foreign key references a primary key in another table and
establishes a relationship between the two tables while maintaining
referential integrity.
8. Which SQL command is used to modify existing records in a table?
A. INSERT
B. UPDATE
C. ALTER
D. MODIFY
Rationale: The UPDATE statement changes existing rows in a table.
INSERT adds new records, while ALTER changes the structure of
database objects.
9. What is the main purpose of a database transaction?
A. Compress database files
B. Create user accounts
C. Execute a group of operations as a single logical unit
D. Remove duplicate tables
Rationale: Transactions group multiple database operations together so
they can succeed or fail as one unit, preserving data integrity.
