Impromptu is a reporting tool, like the report builder in Power Play. Power Play Transformer, however, is a tool which constructs cubes. If Cognos had the mindset, they could enhance Impromptu to report against cubes as well as against relational databases through catalogs. Instead, they have a separate reporter in Power Play. In addition to aggregating data as MDX'er pointed out, cubes are very efficient in the handling of empty cells. A good example of empty cells would be at the intersection of hospital procedure and patient gender. At the intersection of these dimensions, you would not have any male pregnancies nor female prostage sugeries. Another example of empty cells might be sales of bagged ice by zip code in Alaska in the winter. Lots of nothing going on there !!!!
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The trouble with doing something right the first time is that noboby appreciates how difficult it was.
- Steven Wright