thinQmaster Virtual testing partner Adaptive practice exams that find your weak spots and drill them. Every answer explained. From $69
Enroll

thinQmaster

Find your exam

Five questions free, before you decide.

Step 1 · choose a vendor

In one of our camps? Your practice exams come with the tuition — they are on your study page already.

Data & Analytics · Intermediate

Data Analysis Expressions (DAX)

The formula language of Power BI, Analysis Services Tabular and Power Pivot, used for measures, calculated columns, calculated tables and security rules.

Definition

DAX works over tables and relationships, with evaluation driven by filter context and row context. Key functions include CALCULATE, FILTER, ALL, RELATED, SUMX and the time intelligence family. Variables (VAR ... RETURN) improve readability and performance.

Example

Total Sales = SUMX(Sales, Sales[Qty] * Sales[UnitPrice])

Exam tip

Understanding filter context versus row context is the core of every DAX question.

Related terms