Optimizing conditions involving blank values in DAX
This article describes how blank values considered in a DAX conditional expression can affect its query plan and how to apply possible optimizations to improve performance in these cases.
An important metric to consider in optimizing DAX is the cardinality of the data structures iterated by the formula engine. Sometimes the formula engine needs to scan huge datacaches because it cannot leverage the auto-exist logic of DAX. Optimizing these scenarios requires a deep understanding of the DAX engine. This article describes an example of such optimization.