Professional Microsoft® SQL Server® Analysis Services 2008 with MDX

3.6. MDX Functions

MDX functions can be used in MDX expressions or in MDX queries. MDX forms the bedrock of Analysis Services 2008. BIDS builds MDX expressions that typically include MDX functions to retrieve data from the Analysis Services database based upon your actions like browsing dimensions or cubes. MDX functions help address some of the common operations that are needed in your MDX expressions or queries including ordering tuples in a set, counting the number of members in a dimension, and string manipulation required to transform user input into corresponding MDX objects.

This section splits the MDX functions into various categories and provides some basic examples. The best way to learn MDX functions is to understand their use in business scenarios so that you can apply the right MDX function in appropriate situations. In this book, you will often see the MDX that the product generates. Paying attention to and experimenting with such MDX is critical to your transition from basic understanding of Analysis Services 2008 to complete mastery — and, though it is a profound challenge, mastery is attainable. You can do it. Again, when you slice a dimension in any cube-viewing software, like Office Web Components, it is MDX that is generated and executed to retrieve the results. Also, when you create a report based on a cube (UDM) using Excel (as you see in Chapter 17) or using Reporting Services (Chapter 20), it is MDX that is created behind the scenes to capture the contents ...