Tom Chester and Associates

This is an example of a calculation dimension built in Analysis Services 2000. A calculation dimension is a special dimension for the sole purpose of containing MDX calculations.

The download is a 22k zip file containing:

• OLAP cab
• Access database

Why a Calculation Dimension?

A calculation dimension is potentially applicable when a cube contains multiple measures. By building calculations in a separate dimension, there is an intersection point with all measures, reducing the number of calculations that must be built.

If your cube contains only one measure there is no benefit to a calculation dimension.

Installation

You need to know your way around Analysis Manager. If these terse instructions are confusing then this download is not intended for you.

1. unzip anywhere
2. restore the OLAP cab
3. edit the data source to point to the .mdb file

Key Points

• a foreign key for the calculation dimension is added to the fact table courtesy of a view (Access query)
• member 1 of the calculation dimension represent the "just the cube", no calculation; it is the only physical member
• the example year-to-date calculation operates against all measures

This is a trivial example. You can do interesting things with a calculation dimension. For instance, it can be a parent/child dimension, allowing organization and navigation of calculations.