MDX Essentials: Structure of the MDX Data Model

This is the second article of the series, MDX Essentials. The primary focus of this series will be an introduction to the MDX language. The series is designed to provide hands-on application of the fundamentals of the Multidimensional Expressions (MDX) language, with each tutorial progressively adding features designed to meet specific real-world needs.

For more information about the series in general, as well as the software and system requirements needed for getting the most out of the series, please see the first article, MDX at First Glance: Introduction to MDX Essentials.

What We Accomplished in our Last Article

In the first article of the series, we introduced the MDX query in its simplest form. We took a look at some of the basic keywords and then began a discussion of the element(s) of the MDX language that will carry forward as we progress through the series. We performed practice activities, as we will do throughout the entire MDX Essentials series, to reinforce the concepts we introduced.

We explored the rudiments of MDX queries from a syntax perspective and introduced the respective semantics as they arose. We provided a brief introduction to MDX, and then discussed several basic keywords commonly used within its syntax. We examined a breakdown of a simple MDX query into its component parts, comparing and contrasting MDX to SQL where useful. Finally, we created and executed basic MDX queries that served to both demonstrate and reinforce our discussions surrounding keywords and components.

Introduction to the Structure of the MDX Data Model

In this article, we will introduce the MDX data model, together with numerous of its most basic and most common components. These components will include tuples, axes, and sets. We will focus on the composition and uses of, and provide hands-on exposure to, these syntactical building blocks. Rules of syntax will be emphasized and will provide a basis for more complex query building as we progress through the series. Finally, we will work practice exercises to demonstrate tangible results, and to reinforce our discussions with examples.

This lesson will include:

• A brief discussion of tuples and sets, the building blocks of MDX queries;
• An examination of axes and their role in the data model;
• A examination of general MDX query results;
• Illustrations and examples of the concepts presented throughout the session.

Let's begin by discussing the MDX data model and the components that underpin it, with an eye toward gaining a grasp of how the respective elements work and interact to provide us with the robust functionality that is the MDX language.

Page 2: The Building Blocks: Tuples and Sets