MDX in Analysis Services: Named Sets in MDX: An Introduction
March 22, 2004
About the Series ...
This is the thirteenth tutorial article of the series, MDX in Analysis Services. The series is designed to provide hands-on application of the fundamentals of MDX from the perspective of MS SQL Server 2000 Analysis Services ("MSAS,"); our primary focus is the manipulation of multidimensional data sources, using MDX expressions, in a variety of scenarios designed to meet real-world business intelligence needs.
For more information on the series, as well as the hardware / software requirements to prepare for the tutorials we will undertake, please see the first lesson of this series, MDX Concepts and Navigation.
Note: At the time of writing, Service Pack 3 updates are assumed for MSSQL Server 2000, MSSQL Server 2000 Analysis Services, and the related Books Online and Samples. The screen shots that appear in this article were taken from a Windows 2003 Server, and may appear somewhat different from coinciding views in other operating systems.
With this lesson, we will begin an examination of named sets, from the perspective the MDX query language. We obtained brief exposure to the concept of named sets earlier in the series (Using Sets in MDX Queries), touching upon them from the perspective of the MSAS Analysis Manager, the Cube Editor, and related interfaces in MSAS. We will be focusing in this lesson upon named sets that we create within an MDX query, through the use of the WITH statement.
Named sets are in most ways similar to calculated members (See Calculated Members: Introduction and Calculated Members: Further Considerations and Perspectives, both within the MDX in Analysis Services series), as we shall see. The syntax shared by the two is almost identical: we are required to name the set and to provide the specifications for its calculation inside the WITH clause, just as we must perform these steps for a calculated member.
In this article, we will introduce the concepts behind named sets, and then discuss the MDX syntax used in their creation. Next, we will undertake illustrative practice examples, based upon hypothetical business needs, and assembled step-by-step, to illustrate the value that named sets can offer us. Within the context of each step, we will discuss the results we obtain, to reinforce the subject matter in a way that activates the concepts involved, as well as to perhaps suggest expanded uses in our own business environments.