Multidimensional eXpression, calculated members, and Named Sets

In every business, you will face situations where something new came from the business requirements that you didn't consider while designing the data warehouse. On the other hand, sometimes the requirements cannot be fulfilled in the data warehouse and should be fulfilled in the cube.

SSAS provides a way to create calculated members based on an expression language named Multidimensional eXpression (MDX). MDX is the query language for SSAS; all queries from the client applications are sent to the SSAS server as an MDX query, and the result of that query will be returned in a multidimensional format.

As an example for calculation of the members, assuming that you want to calculate the product of the unit price and the item quantity, you can create a calculated member for that. Also, sometimes you might require a subset of a dimension attribute, for example, a list of the top 10 customers in a specific area. The Named Set in SSAS provides the ability to create these kinds of subsets.