Microsoft Power BI DAX Formulas and Functions

Question 1

What does the DAX function CALCULATE() do?

Accepted Answer

Evaluates an expression in a modified filter context

Answer

Performs mathematical calculations on columns

Answer

Counts rows in a table

Answer

Returns a value from a related table

Question 2

What is the result of the DAX expression SUMX(Sales, Sales[Quantity] * Sales[Price])?

Accepted Answer

The row-by-row product of Quantity and Price, summed across all rows

Answer

The sum of the Quantity column

Answer

The average of Quantity times Price

Answer

A count of rows where Quantity times Price is not blank

Question 3

What does ALL() do when used inside CALCULATE()?

Accepted Answer

Removes filters from the specified table or columns

Answer

Applies all slicers to the calculation

Answer

Adds all rows to the calculation

Answer

Returns all unique values in a column

Question 4

What is the difference between DISTINCTCOUNT() and COUNT() in DAX?

Accepted Answer

DISTINCTCOUNT counts unique non-blank values; COUNT counts all non-blank values including duplicates

Answer

COUNT counts blanks; DISTINCTCOUNT does not

Answer

They are identical in behavior

Answer

COUNT only works on numeric columns; DISTINCTCOUNT works on text

Question 5

In DAX, what does the RELATED() function do?

Accepted Answer

Returns a value from a related table by following an existing relationship

Answer

Creates a new relationship between tables

Answer

Lists all related tables in the model

Answer

Filters a related table

Question 6

What does the DAX function DIVIDE(numerator, denominator, alternateResult) do differently than simply using the / operator?

Accepted Answer

It returns the alternateResult (default 0) instead of an error when dividing by zero

Answer

It rounds the result to two decimal places

Answer

It only works with integer values

Answer

It performs integer division