MDX Solutions: With Microsoft® SQL Server™ Analysis Services 2005 and Hyperion® Essbase, Second Edition

Chapter 2. Introduction to MDX Calculated Members and Named Sets

In addition to selecting data, MDX provides the ability to define new calculations, and to define named sets of tuples that can be referred to in other selections and functions. These can be done within a query, which frees the database developer from needing to account for all applications of the database, and it frees the users and/or applications from relying on the database for all calculations and set or filter definitions. In this chapter, we introduce youto creating calculations using the MDX construct called "calculated members." Calculated members are a form of DDL (data definition language) that servers such as Analysis Services and Essbase allow to be defined as part of the database as well as part of a query. The way they behave is the same in either case, so we will look at how they behave from the point of view of queries. We will also introduce you to creating named sets.

Servers such as Analysis Services and Essbase also allow MDX-based calculations to be defined at the database, and Analysis Services allows them to be defined within a client session as well. Analysis Services also allows named sets to be defined at the server. Essbase 9 provides an alternate technique to accomplish the same result within MDX queries, which will be discussed in that section.

Dimensional Calculations As Calculated Members

If you have some experience with SQL, you will find that the numerical calculations that are straightforward ...