WGU D313 ADVANCED DATA MANAGEMENT EXAM
QUESTIONS AND 100% VERIFIED ANSWERS (NEW)
300 QUESTIONS AND ANSWERS
1. What is the purpose of database normalization? Answer: Database
normalization is the process of organizing data in a database to reduce
redundancy and dependency, improving data integrity and reducing storage
space.
2. What is First Normal Form (1NF)? Answer: 1NF requires that each
column contains atomic (indivisible) values, and each record is unique with no
repeating groups.
3. What is Second Normal Form (2NF)? Answer: 2NF requires that the table
is in 1NF and all non-key attributes are fully functionally dependent on the
primary key.
4. What is Third Normal Form (3NF)? Answer: 3NF requires that the table is
in 2NF and all attributes are directly dependent on the primary key, with no
transitive dependencies.
5. What is Boyce-Codd Normal Form (BCNF)? Answer: BCNF is a stricter
version of 3NF where every determinant must be a candidate key.
6. What is a functional dependency? Answer: A functional dependency exists
when one attribute uniquely determines another attribute in a relation.
7. What is a partial dependency? Answer: A partial dependency occurs when
a non-key attribute depends on only part of a composite primary key.
8. What is a transitive dependency? Answer: A transitive dependency occurs
when a non-key attribute depends on another non-key attribute, which depends
on the primary key.
,9. What is denormalization and when is it used? Answer: Denormalization is
the process of intentionally introducing redundancy to improve query
performance, typically used in data warehousing and reporting systems.
10. What is an entity-relationship diagram (ERD)? Answer: An ERD is a
visual representation of entities, their attributes, and relationships in a database
system.
11. What is cardinality in database relationships? Answer: Cardinality
defines the number of instances of one entity that can be associated with
instances of another entity (one-to-one, one-to-many, many-to-many).
12. What is a weak entity? Answer: A weak entity is an entity that cannot be
uniquely identified by its own attributes and depends on a strong entity for
identification.
13. What is a composite key? Answer: A composite key is a primary key that
consists of two or more attributes used together to uniquely identify a record.
14. What is a surrogate key? Answer: A surrogate key is an artificial key
created to uniquely identify records when no natural key exists or when a
natural key is too complex.
15. What is referential integrity? Answer: Referential integrity ensures that
foreign key values in one table correspond to valid primary key values in the
referenced table.
16. What is domain integrity? Answer: Domain integrity ensures that all
values in a column fall within the defined domain (data type, range, format).
17. What is entity integrity? Answer: Entity integrity ensures that no primary
key value can be null and that each primary key value is unique.
18. What is the difference between logical and physical database design?
Answer: Logical design focuses on the structure and relationships without
considering implementation details, while physical design involves specific
DBMS implementation decisions.
19. What is a business rule in database design? Answer: A business rule is a
constraint or guideline that governs how data should be stored, processed, or
maintained based on business requirements.
20. What is the purpose of database constraints? Answer: Database
constraints enforce business rules and maintain data integrity by restricting the
type of data that can be stored in tables.
, 21. What is a check constraint? Answer: A check constraint validates data by
ensuring that values in a column meet specific conditions before being stored.
22. What is a unique constraint? Answer: A unique constraint ensures that all
values in a column or combination of columns are distinct across all rows in the
table.
23. What is a not null constraint? Answer: A not null constraint ensures that a
column cannot contain empty values.
24. What is a foreign key constraint? Answer: A foreign key constraint
maintains referential integrity by ensuring that values in a column correspond to
valid values in the referenced table's primary key.
25. What is the difference between DELETE and TRUNCATE? Answer:
DELETE removes specific rows and can be rolled back, while TRUNCATE
removes all rows faster but cannot be rolled back and resets identity counters.
26. What is a database schema? Answer: A database schema is the logical
structure that defines how data is organized, including tables, columns,
relationships, and constraints.
27. What is data modeling? Answer: Data modeling is the process of creating
a conceptual representation of data structures and their relationships within a
system.
28. What is a conceptual data model? Answer: A conceptual data model
represents high-level business concepts and relationships without
implementation details.
29. What is a logical data model? Answer: A logical data model provides
more detail than conceptual models, including attributes and relationships, but
remains independent of specific DBMS.
30. What is a physical data model? Answer: A physical data model includes
implementation-specific details such as data types, indexes, and storage
requirements for a particular DBMS.
31. What is an attribute in database design? Answer: An attribute is a
property or characteristic of an entity that describes some aspect of the entity.
32. What is the difference between a primary key and a candidate key?
Answer: A candidate key is any column or combination of columns that can
uniquely identify a row, while a primary key is the chosen candidate key for the
table.
QUESTIONS AND 100% VERIFIED ANSWERS (NEW)
300 QUESTIONS AND ANSWERS
1. What is the purpose of database normalization? Answer: Database
normalization is the process of organizing data in a database to reduce
redundancy and dependency, improving data integrity and reducing storage
space.
2. What is First Normal Form (1NF)? Answer: 1NF requires that each
column contains atomic (indivisible) values, and each record is unique with no
repeating groups.
3. What is Second Normal Form (2NF)? Answer: 2NF requires that the table
is in 1NF and all non-key attributes are fully functionally dependent on the
primary key.
4. What is Third Normal Form (3NF)? Answer: 3NF requires that the table is
in 2NF and all attributes are directly dependent on the primary key, with no
transitive dependencies.
5. What is Boyce-Codd Normal Form (BCNF)? Answer: BCNF is a stricter
version of 3NF where every determinant must be a candidate key.
6. What is a functional dependency? Answer: A functional dependency exists
when one attribute uniquely determines another attribute in a relation.
7. What is a partial dependency? Answer: A partial dependency occurs when
a non-key attribute depends on only part of a composite primary key.
8. What is a transitive dependency? Answer: A transitive dependency occurs
when a non-key attribute depends on another non-key attribute, which depends
on the primary key.
,9. What is denormalization and when is it used? Answer: Denormalization is
the process of intentionally introducing redundancy to improve query
performance, typically used in data warehousing and reporting systems.
10. What is an entity-relationship diagram (ERD)? Answer: An ERD is a
visual representation of entities, their attributes, and relationships in a database
system.
11. What is cardinality in database relationships? Answer: Cardinality
defines the number of instances of one entity that can be associated with
instances of another entity (one-to-one, one-to-many, many-to-many).
12. What is a weak entity? Answer: A weak entity is an entity that cannot be
uniquely identified by its own attributes and depends on a strong entity for
identification.
13. What is a composite key? Answer: A composite key is a primary key that
consists of two or more attributes used together to uniquely identify a record.
14. What is a surrogate key? Answer: A surrogate key is an artificial key
created to uniquely identify records when no natural key exists or when a
natural key is too complex.
15. What is referential integrity? Answer: Referential integrity ensures that
foreign key values in one table correspond to valid primary key values in the
referenced table.
16. What is domain integrity? Answer: Domain integrity ensures that all
values in a column fall within the defined domain (data type, range, format).
17. What is entity integrity? Answer: Entity integrity ensures that no primary
key value can be null and that each primary key value is unique.
18. What is the difference between logical and physical database design?
Answer: Logical design focuses on the structure and relationships without
considering implementation details, while physical design involves specific
DBMS implementation decisions.
19. What is a business rule in database design? Answer: A business rule is a
constraint or guideline that governs how data should be stored, processed, or
maintained based on business requirements.
20. What is the purpose of database constraints? Answer: Database
constraints enforce business rules and maintain data integrity by restricting the
type of data that can be stored in tables.
, 21. What is a check constraint? Answer: A check constraint validates data by
ensuring that values in a column meet specific conditions before being stored.
22. What is a unique constraint? Answer: A unique constraint ensures that all
values in a column or combination of columns are distinct across all rows in the
table.
23. What is a not null constraint? Answer: A not null constraint ensures that a
column cannot contain empty values.
24. What is a foreign key constraint? Answer: A foreign key constraint
maintains referential integrity by ensuring that values in a column correspond to
valid values in the referenced table's primary key.
25. What is the difference between DELETE and TRUNCATE? Answer:
DELETE removes specific rows and can be rolled back, while TRUNCATE
removes all rows faster but cannot be rolled back and resets identity counters.
26. What is a database schema? Answer: A database schema is the logical
structure that defines how data is organized, including tables, columns,
relationships, and constraints.
27. What is data modeling? Answer: Data modeling is the process of creating
a conceptual representation of data structures and their relationships within a
system.
28. What is a conceptual data model? Answer: A conceptual data model
represents high-level business concepts and relationships without
implementation details.
29. What is a logical data model? Answer: A logical data model provides
more detail than conceptual models, including attributes and relationships, but
remains independent of specific DBMS.
30. What is a physical data model? Answer: A physical data model includes
implementation-specific details such as data types, indexes, and storage
requirements for a particular DBMS.
31. What is an attribute in database design? Answer: An attribute is a
property or characteristic of an entity that describes some aspect of the entity.
32. What is the difference between a primary key and a candidate key?
Answer: A candidate key is any column or combination of columns that can
uniquely identify a row, while a primary key is the chosen candidate key for the
table.
