Dimensional Modeling Question

Hello:
I am new to dimensional modeling and trying to design a model based on the existing OLTP system.
Below are the links to ERDs for existing OLTP system and a dimension model that I have developed. Can someone expert in this area take a quick look and offer me suggestions please? It won't take much time as the model is simple. I am especially worried about the inclusion of bridge table STORE_DEPARTMENT in the model and the dimension tables referencing other dimension tables. Is this normal or I am doing it wrong? I am trying to check if the model can answer some of the DSS questions but your suggestions would really help me if I am going in a wrong direction.
Thanks in advance for your help :)
Regards,
Ramesh

Hi,
There is a trade off on the availability and the Complex analytics.
A star schema is good if you have the functional requirements really simple. Like the dimension is not SCD Type2 (slowly changing dimension) and you don't need to do "AS IS" vs "AS WAS" reporting.
In modern Analytics in any domain dimensions are SCD Type 2 as business keep on evolving. In a star schema structure this will cause explosion of data if there are frequent changes at the higher levels of the dimensional hierarchy. That anyway will hit the performance.
As far as my experience goes, at the data model level it is better to have snow flaked dimensions. and while managing the metadata (in a BI reporting tool) you can consolidate the snowflaked dimensions in star schema structures. That will make ah hoc analytics much simple for the business users.
A lot of performance measure can be taken to improve the end user experience.
In short the trend in BI analytics demands to have a snowflaked structure rather than a simple star schema structure.
Hope this helps.

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