Many to Many Relationships in DAX Explained

There is a lot to learn in DAX if you want to be a ninja.  A couple of the more complex and important things to learn and understand are filter propagation and context transition.  It is not so much that you need to be a rocket scientist to understand these concepts, it is more that they are not naturally intuitive.  You simply have to learn how filter propagation and context transition work.  What’s more, if you have a Excel background, there are some fundamental differences between the way Power Pivot works vs regular Excel, and you have to learn these things too.  All these things are learnable – but indeed you will need to learn. You need an understanding of filter propagation and context transition to understand how to solve the Many to Many problem below – but don’t worry – I will explain it in detail in this post.

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