Module quiz: Transforming data in Power BI :Extract, Transform and Load Data in Power BI (Microsoft Power BI Data Analyst Professional Certificate) Answers 2025

Question 1

A join is a method to combine ________ from two or more tables based on ________.

❌ “columns” and “a common value”
✅ “rows” and “a related column”
❌ “datasets” and “a specific attribute”

Explanation:
A join matches rows from different tables using a related column (join key).

Question 2

The FeatureID column is Whole Number in one table and Text in another. What should you do?

❌ Try to append tables and create an expanded list.
✅ Change the column type of FeatureID to Whole Number in ProductFeature table.
❌ Change the column type of FeatureID to Text in Feature table.

Explanation:
To merge tables, matching columns must have the same data type.

Question 3

True or False: A join key is a column that exists in only one table being joined.

❌ True
✅ False

Explanation:
A join key must exist in both tables.

Question 4

True or False: In Power BI, the left join type includes all rows from both tables, including unmatched rows.

❌ True
✅ False

Explanation:
A left join keeps all rows from the left table and only matching rows from the right table.

Question 5

What is the purpose of combining tables with the merge operation?

❌ To create a new table with new columns.
❌ To remove duplicate rows from a single table.
✅ To combine data from multiple tables into a table based on matching values.

Explanation:
Merge is used to combine tables using matching column values.

Question 6

Which option can be considered the purpose of a join operation?

❌ Ensuring consistency
❌ Creating insights from data
✅ Adding new relationships

Explanation:
Joins are used to connect related tables.

Question 7

When merging two tables, which conditions are required? (Select all that apply)

❌ Matching columns should have a numeric data type.
✅ Matching columns should have convertible data types.
✅ Matching columns should have the same data type.

Explanation:
Matching columns must be compatible and of the same data type.

Question 8

In Power BI, data transformation involves ____________.

✅ cleaning, filtering, and manipulating data
❌ creating visualizations and reports
❌ importing data from external sources

Explanation:
Transformation prepares data for analysis by cleaning and shaping it.

Question 9

What is the purpose of cleaning and formatting data in Power BI?

❌ Creating visualizations and reports.
✅ Removing inconsistencies and errors in the data.
❌ Creating reports and dashboards.

Explanation:
Cleaning ensures accurate and reliable data.

Question 10

Two tables are related by SalesID, and date data exists in the second table. What should you do to visualize the date column?

❌ To merge columns
✅ To join two tables
❌ To format data

Explanation:
You must join the tables to use related data in visualizations.

🧾 Summary Table