business-intelligencecubesrolap

Cube design - ROLAP considerations vs. MOLAP


Does anyone have resources that give a list of things to consider when designing a ROLAP cube, as opposed to MOLAP (I'm doing it in Pentaho, but I guess the principles are not dis-similar for other implementations). For example, I'm thinking of things like:

  1. should extra transformational work be done at the ETL stage to reduce computational work when querying the cube?

  2. should all my dimension tables be in the same database as my cube?


Solution

  • I'm a Pentaho implementor in Indonesia. First, of course you should try to aggregate all your measures group by surrogate keys involved.

    And in Mondrian, you can "cache" some computations using additional aggregate tables. You can do it in Pentaho Aggregate Designer. But after that you will need additional work in your data warehouse / ETL stage.

    Regards,

    Feris

    http://pentaho-en.phi-integration.com