Parameters in Power BI - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Purpose of Parameters in Power BI

What is the main purpose of using parameters in Power BI reports?

A To create complex calculated columns that update automatically

B To permanently store data in the Power BI dataset for faster queries

C To automatically refresh data sources on a schedule

D To allow users to dynamically change filter values or inputs without editing the report directly

💡 Hint

Think about how parameters help users interact with reports without changing the underlying data.

Parameters let report users input or select values that control filters or calculations dynamically, making reports flexible and interactive.

❓ dax_lod_result

intermediate

DAX Measure Using Parameter for Sales Threshold

Given a parameter named SalesThreshold with value 10000, what is the result of this DAX measure?

High Sales Count = CALCULATE(COUNTROWS(Sales), Sales[Amount] > SalesThreshold)

Assuming the Sales table has 3 rows with Amounts: 8000, 12000, 15000.

A 0

B 2

C 1

D 3

💡 Hint

Count rows where Amount is greater than 10000.

Only the rows with 12000 and 15000 are greater than 10000, so count is 2.

❓ visualization

advanced

Using Parameters to Create Dynamic Titles

You want to create a dynamic report title that changes based on a parameter SelectedYear. Which approach correctly uses the parameter in a DAX measure for the title?

A Report Title = "Sales Report for " & SelectedYear

B Report Title = CONCATENATE("Sales Report for ", SelectedYear)

C Report Title = "Sales Report for " & FORMAT(SelectedYear, "0")

D Report Title = "Sales Report for " + SelectedYear

💡 Hint

Remember to convert numeric parameters to text before concatenation.

Using FORMAT converts the numeric parameter to text, allowing safe concatenation with strings.

🎯 Scenario

advanced

Scenario: Filtering Data with Parameters in Power Query

You want to filter a table in Power Query based on a parameter RegionParam. Which M code snippet correctly applies this filter?

A FilteredTable = Table.SelectRows(Source, each [Region] = RegionParam)

B FilteredTable = Table.SelectRows(Source, each RegionParam = [Region])

C FilteredTable = Table.SelectRows(Source, each [Region] <> RegionParam)

D FilteredTable = Table.SelectRows(Source, each Text.Contains([Region], RegionParam))

💡 Hint

Check the syntax for filtering rows where the column equals the parameter.

The correct syntax uses each [Column] = Parameter to filter rows matching the parameter value.

🔧 Formula Fix

expert

Debugging Parameter Usage in DAX Measure

Consider this DAX measure using a parameter DiscountRate:

Final Price = SUM(Sales[Price]) * (1 - DiscountRate)

When running the report, the measure returns an error. What is the most likely cause?

A DiscountRate is a parameter but used without wrapping in a function like SELECTEDVALUE

B SUM(Sales[Price]) cannot be multiplied by a parameter

C DiscountRate parameter must be declared inside the measure

D The measure syntax is invalid because of missing CALCULATE

💡 Hint

Parameters in DAX measures often need to be wrapped to get their current value.

Parameters are not automatically scalar values in DAX; you often need SELECTEDVALUE or similar to retrieve their value.