CALCULATE in DAX is such a powerful and complex function to fully understand.  In essence what CALCULATE will do is modify the current filter context.  And it does this by evaluating both the current filter context and the filters applied by CALCULATE. The syntax for CALCULATE is: =CALCULATE ([Expression], filter1, filter2…..) So if CALCULATE contains […]

Context Transition in DAX for PowerPivot, Power BI & SSAS

Context Transition in DAX is when you transform the row context into the filter context.  In order to understand Context Transition a practical knowledge of Row and Filter context is needed, along with a practical knowledge of CALCULATE. Understanding Context Transition is not too complicated, however it is something that DAX users get caught out […]

Related and RelatedTable – DAX for Power Pivot, Power BI and SSAS

When we looked at the SUM and SUMX expressions in an earlier article and video we introduced the use of RELATED. You will remember this expression; =[Qty] * RELATED(products[Sales Price]) Where we took the qty sold from the sales table and we went across to the related products table and found the relevant sales price […]

DAX COUNT and COUNTX – Impact of Using Measures and Columns

In a previous post we looked at DAX SUM and SUMX  expressions and you were introduced to a lot.  We mentioned table functions, iterators, row and filter context, measure, columns, and we also quickly introduced you to the RELATE function. In this article we are going to slow things down a little and look at DAX […]

What is DAX


Data Analysis Expression language or DAX, was originally released with Power Pivot in Excel in 2010 by Microsoft. It’s a functional language that is very similar to excel, as you would expect as it was part of the excel tools.  Its initial basic function was to allow excel users solve more complex business problems. Now, […]

DAX SUM and SUMX functions

DAX SUM and SUMX Functions

The role of both DAX SUM and SUMX functions are to add numerical data together.  Yet both these functions are rather different. Lets talk about the SUM function first.  The SUM function is simple.  It takes a column of data and adds the values to give a total.  The syntax is SUM().  It works like the […]

DAX Divide Function

DAX for Power BI and Power Pivot – DAX Divide Function

When you are working in Excel it is relatively easy to divide two numbers. You take the value from one cell, and divide it by the value or the in another cell.  For Example =B3/B2.  Divide is a basic mathematical operator. In Excel if you try to divide a value by zero you will get the error […]