DMC Conceptual and Logical Data Design

Question 1

Which of the following best distinguishes a logical data model from a conceptual data model?

Accepted Answer

A logical model adds attributes, primary keys, and data types without specifying a DBMS

Answer

A logical data model refines the conceptual model by adding detailed attributes, primary and foreign keys, and data types while remaining DBMS-independent.

Question 2

In logical data modeling, what is normalization primarily used to achieve?

Accepted Answer

Eliminate data redundancy and update anomalies

Answer

Normalization is the process of organizing data to eliminate redundancy and dependency anomalies, ensuring each fact is stored in one place.

Question 3

What is a functional dependency in the context of normalization?

Accepted Answer

A situation where the value of one attribute determines the value of another

Answer

A functional dependency (A → B) means that knowing the value of attribute A uniquely determines the value of attribute B.

Question 4

Which normal form eliminates partial dependencies on a composite primary key?

Accepted Answer

Second Normal Form (2NF)

Answer

2NF requires that every non-key attribute is fully functionally dependent on the entire primary key, eliminating partial dependencies.

Question 5

Third Normal Form (3NF) eliminates which type of dependency?

Accepted Answer

Transitive dependencies

Answer

3NF removes transitive dependencies, ensuring that non-key attributes depend only on the primary key and not on other non-key attributes.

DMC - Data Modeling Certification Practice Test

DMC - Data Modeling Certification Practice Test

DMC Conceptual and Logical Data Design