When accessing a tabular data source there may be some differences to multidimensional cubes.
You can define new measures in the cube on the fly.
To do this, select the Measures dimension in the report designer. Drag an attribute from the Available hierarchies into the Selections area to the right of the normal measures list.
Once it's been added, you can select the aggregation type, Sum/Average/Min/Max for numeric attributes, Counts for other types.
