DAX (Data Analysis Expression) is a language used in Power Pivot, Power BI and SQL Analysis Services.

It is similar to Excel formulas, but different in many ways.

Three ways of DAX use in Power Pivot or Power BI

New column creation

  • Creation of a new column, which is based on other columns. The formula looks like this:
    =[Revenue]*0,5

Measure creation

  • Creation of measure, like sum or average of whole column. In this case the data are typed below the table in Power Pivot or in New Measure in Power BI.
    The formula is like this:
    =SUM([Revenue])

New table creation

You can use DAX function to create a new table, which works like a view in database – does not contain any data, just presents data from other tables.
The formula is like this:
List of items = DISTINCT(‘original data'[Goods]) 
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