Dimensional applications are best and most easily built using a dimensional language. These dimensional applications are typified by the related notions of OLAPand dimensional data warehouses and marts. MDX (for MultiDimensional eXpressions) is the most widely accepted software language used for these applications. The book you read here, MDX Solutions, is the second edition of a guide to learning and using MDX. Since the first edition of MDX Solutions, the number of analytical applications that use MDX has grown very large, and several more servers and many third-party and homegrown client tools now allow you to use MDX to express the logic you use to calculate and to retrieve your information.
As a language, MDX is rather different in style and feel from SQL, and quite different from other programming languages like C++, C#, Lisp, Fortran, and so on. You can think of the formula language of a spreadsheet like Excel as another programming language, and while it is different than Excel, characterizing MDX as a sort of Excel-like SQL or a SQL-like Excel seems more apt than any other analogy. (If you’re familiar with other OLAP query or calculation languages, it has more in common with them, but many readers will not be.)