10 Multiple Choice Questions (MCQs) related to Data Modeling in Power BI

1. What is the primary purpose of data modeling in Power BI?

A) To create visualizations only
B) To structure relationships between tables for efficient analysis
C) To import data from external sources
D) To replace the need for SQL databases

✅ Answer: B) To structure relationships between tables for efficient analysis

2. Which statement is true about fact tables and dimension tables?

A) Fact tables store descriptive attributes, while dimension tables store numeric data
B) Dimension tables store descriptive attributes, while fact tables store numeric data
C) Both fact and dimension tables store only numerical data
D) Fact tables store unstructured data

✅ Answer: B) Dimension tables store descriptive attributes, while fact tables store numeric data

3. What is the key advantage of using a Star Schema in Power BI?

A) Reduces data redundancy but increases query complexity
B) Improves query performance and simplifies relationships
C) Requires more relationships to connect tables
D) Avoids the need for a date dimension

✅ Answer: B) Improves query performance and simplifies relationships

4. In Power BI, what type of relationship is most commonly used between a fact table and a dimension table?

A) One-to-One (1:1)
B) One-to-Many (1:)
C) Many-to-Many (:*)
D) Circular Relationship

✅ Answer: B) One-to-Many (1:*)

5. What is cardinality in Power BI data modeling?

A) The number of visualizations on a dashboard
B) The number of rows in a dataset
C) The uniqueness of values in a column and its impact on performance
D) The way colors are represented in charts

✅ Answer: C) The uniqueness of values in a column and its impact on performance

6. How can you create a Date Dimension in Power BI?

A) Using SQL scripts only
B) Using the CALENDAR() or CALENDARAUTO() DAX functions
C) By manually entering dates into an Excel file
D) By creating multiple relationships between tables

✅ Answer: B) Using the CALENDAR() or CALENDARAUTO() DAX functions

7. What is the primary difference between a calculated column and a measure in Power BI?

A) Calculated columns are stored in the table, while measures are dynamically calculated
B) Measures require additional storage, while calculated columns do not
C) Calculated columns cannot be created using DAX
D) Measures can only be used in Power Query

✅ Answer: A) Calculated columns are stored in the table, while measures are dynamically calculated

8. How can Many-to-Many relationships be handled in Power BI?

A) By creating a bridge table
B) By duplicating the dimension tables
C) By using the SUM function in DAX
D) By creating One-to-One relationships

✅ Answer: A) By creating a bridge table

9. Which of the following is NOT a method to optimize Power BI data models?

A) Removing unnecessary columns
B) Using a Snowflake Schema instead of a Star Schema
C) Reducing cardinality in high-cardinality columns
D) Using pre-aggregated data

✅ Answer: B) Using a Snowflake Schema instead of a Star Schema

10. What function is used to implement Row-Level Security (RLS) dynamically?

A) CALCULATE()
B) FILTER()
C) USERPRINCIPALNAME()
D) RELATEDTABLE()

✅ Answer: C) USERPRINCIPALNAME()