What is DAX?

Reading Time: 8 Mins | Level: Beginner to Advanced

1. What is DAX (Data Analysis Expressions)?

DAX is the native formula and query language developed by Microsoft for Power BI, Analysis Services, and Excel Power Pivot.

While DAX looks similar to Excel spreadsheet formulas (it shares functions like SUM, AVERAGE, and IF), DAX is fundamentally different:

• Excel formulas calculate over cell references (A1 + B1).
• DAX formulas calculate over entire tables, columns, and relationships under dynamic filter contexts!

2. The Two Core Types of Calculations in DAX

1. 1
   Calculated Columns: Evaluated row-by-row during data refresh. Stored in memory.
2. 2
   Measures: Dynamic formulas calculated on the fly in response to user slicers and visual filters. Zero storage footprint!