Chapter 6. Evaluation Context and CALCULATE
To get the best from DAX, you need to understand the evaluation context. We introduced this terminology when we talked about calculated columns and measures in Chapter 3, mentioning that calculated columns and measures differ mainly in their evaluation context. Now let us look at how the evaluation context is defined, and most important, how it works. In this chapter, we also introduce one of the most important DAX functions: CALCULATE, which allows you to make complex calculations by manipulating the evaluation context.
Understanding the content of this chapter is important if you want to use DAX in Microsoft SQL Server PowerPivot for Excel. Nevertheless, the topics described here are demanding, ...