Data Engineering Data Warehouse Modeling 2

Question 1

In a star schema, what is the central table that contains measurable business metrics called?

Accepted Answer

Fact table

Answer

The fact table sits at the center of a star schema and holds quantitative measures plus foreign keys to dimensions.

Question 2

A snowflake schema differs from a star schema primarily because its dimension tables are:

Accepted Answer

Normalized into multiple related tables

Answer

Snowflake schemas normalize dimensions into multiple related tables, reducing redundancy at the cost of more joins.

Question 3

Which type of fact table stores a row only when an event occurs, such as a single sale?

Accepted Answer

Transaction fact table

Answer

A transaction fact table records one row per discrete business event as it happens.

Question 4

What is the grain of a fact table?

Accepted Answer

The level of detail represented by one row

Answer

Grain defines exactly what a single fact row represents, such as one line item per order.

Question 5

A factless fact table is most commonly used to:

Accepted Answer

Record events or coverage with no numeric measures

Answer

Factless fact tables capture the occurrence of events or relationships without storing numeric measures.

Data Engineering Practice Test