MDX: NonEmpty, Exists and evil NonEmptyCrossJoin
When NonEmptyCrossJoin was introduced in AS2000 it made a lot of people happy. Indeed, this function seemed to be almost magic. It worked wicked fast and seemed to solve all the performance problems with. While the original intention was to be used in MDX SELECT queries generated by (now discontinued) English Query, the function was finding its way as an optimization technique into many scenarios. Here are two typical optimization tips for AS2000
Tags: mdx