Matt Allington explains when to use SUM() or SUMX() in DAX:

Example: Total Sales SUMX = SUMX(Sales,Sales[Qty] * Sales[Price Per Unit])

SUMX() will iterate through a table specified in the first parameter, one row at a time, and complete a calculation specified in the second parameter, eg Quantity x Price Per Unit as shown in the example above for the current filter context.  Once it has done this for every row in the specified table in current filter context, it then adds up the total of all of the row by row calculations to get the total.   It is this total that is returned as the result.

This is a really good explanation of the topic.

Related Posts

Power BI Architecture Diagram V4

Dustin Ryan has a new version of the Power BI Architecture Diagram: First and most importantly, I updated the Power BI logo in the diagram to the latest version of the logo! Secondly, I included Power BI Dataflows in the diagram tagged #6. Power BI Dataflows are used to ingest, transform, integrate, and enrich big […]

Read More

Power BI Violin Plots

Meagan Longoria shows off a violin plot custom visual in Power BI: A violin plot is a nifty chart that shows both distribution and density of data. It’s essentially a box plot with a density plot on each side. Box plots are a common way to show variation in data, but their limitation is that you can’t […]

Read More


July 2017
« Jun Aug »