Finally, another type of TM1 cube is the cube referred to as a lookup or conversion cube. This is a sort of utility cube. Lookup cubes are cubes that you can set up and use to support other cubes and processes within a TM1 application.
These cubes are most often set up to be read-only by design or even made non-visible to TM1 users and may contain calculations, controls, or reference data that are then used in your TM1 processing or pulled into other cubes using TM1 rules.
Keep in mind that before you create a lookup cube, you should review the existing TM1 control cubes to see if the data that is needed is available there.
As in any application there may be a need to share the same data or logic in multiple components of a Cognos TM1 application. Lookup cubes can be used here to eliminate redundancy of reference data used within TM1 cubes and processes on the same TM1 Server.