powerbi - Difference between CALCULATE(m, x=red) vs CALCULATE(m, KEEPFILTERS(x=red))

Question

What is the difference between CALCULATE(m, x=red) and CALCULATE(m, KEEPFILTERS(x=red))

Apparently they are not the same. I found docs and explanation but I still do not get it.

https://docs.microsoft.com/en-us/dax/keepfilters-function-dax

https://dax.guide/keepfilters/

Answer 1

Your first measure, without KEEPFILTERS overrides all other filters applied to field x.

The second measure, using KEEPFILTERS maintains the filter context on field x, and applies the new filter context as a subset of existing filters (or blank, if no overlap of filter contexts).

Here's a simple example PBIX file to demonstrate - play with the colour slicer, and see the difference in the two measures: https://pwrbi.com/so_57850298/

This SQLBI.com article explains it well.