This technical article was generously contributed by Chris Webb, an OLAP guru and independent consultant (check him out at Crossjoin Consulting, or on his blog). Chris also has written a book on MDX called 'MDX Solutions', that you can get here once you are looking to go deep with Mondrian and MDX!
In this series I'll be showing you how to implement some common MDX calculations using the SteelWheelsSales sample cube. In many cases you will be able to take these calculations and, after changing some of the measure and dimension names, be able to re-use them in your own cubes; hopefully you'll also be able to pick up a bit of the theory on the way and be able to tackle more specific problems yourselves. Nicholas Goodman has already given excellent explanations on how to edit the MDX query used by JPivot to display data (http://www.nicholasgoodman.com/bt/blog/2006/06/08/mondrian-power-of-olapmdx-at-your-fingertips/) and how to add calculated members to a Mondrian cube (http://www.nicholasgoodman.com/bt/blog/2006/06/09/mondrian-olap-power-at-your-users-fingertips/) so I won't repeat what he has to say.
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