Free DMC Techniques and Methodologies Questions and Answers

Question 1

Which of the following are key objectives of normalization in data modeling?

Accepted Answer

Reducing data redundancy

Answer

Enhancing database security

Answer

Increasing query execution speed

Question 2

Which of the following best describes the star schema used in dimensional modeling?

Accepted Answer

It uses a central fact table surrounded by dimension tables.

Answer

It contains normalized tables with minimal redundancy.

Answer

It is used exclusively for transactional systems.

Answer

It has no foreign key relationships between tables.

Question 3

What is the primary key in a relational database?

Accepted Answer

A unique identifier for a row in a table.

Answer

A column or set of columns that ensures referential integrity.

Answer

A field used to link two tables together.

Question 4

Which of the following best describes denormalization?

Accepted Answer

A technique used to optimize read performance by combining tables.

Answer

A process of increasing table normalization to 5NF or higher.

Answer

The act of restructuring databases to eliminate foreign keys.

Answer

A process used exclusively in NoSQL databases.

Question 5

Which of the following are common elements of an Entity-Relationship Diagram (ERD)?

Accepted Answer

Entities

Answer

Data Pipelines