Marco Russo and Alberto Ferrari show that tracking weekdays is like an onion:
Computing time intelligence calculations in DAX is rather simple. However, as soon as the requirements are not trivial, the complexity of formulas skyrockets, and it is necessary to have a very good understanding of several details about DAX to obtain a good formula. In this article, we show a simple requirement: the need to maintain a filter on weekdays while computing time intelligence. As you are about to read, it will require several complex steps despite being a simple requirement; but let us start by clarifying what we want to obtain and what a filter-preserving column is.
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