Art Tennick has worked in relational database design and SQL queries for more than 20 years. He has been involved in multi-dimensional database design, cubes, data mining, DMX, and MDX for 10 years. Art is the author of Practical MDX Queries for Microsoft SQL Server Analysis Services 2008, Practical DMX Queries for Microsoft SQL Server Analysis Services 2008, and Practical PowerPivot & DAX Formulas for Excel 2010. His website is www.MrCube.net.