Forum Discussion

Stel's avatar
Stel
Helper I
6 years ago

Using inactive relationship in visuals

Hi all, I have a question about inactive relationships. I have following tables: - fact_order with: - 1 active relationship to dim_customer - 1 active relationship to dim_date (order_date) and 1 ...
Need Help
Stel's avatar
Stel
Helper I
6 years ago

v-kelly-msft  or Greg_Deckler Is it possible to have a look at the model and give me some advice in the active/inactive relationships I need to make between the tables? Or other suggestions?

 

Much appreciated

Anonymous's avatar
Anonymous
Not applicable
6 years ago

Stel, I can tell you right away that the model is faulty. Direct connections between fact tables should never be created. Unless... you want to face troubles later on. Please normalize the model correctly: fact tables must only ever be connected to dimensions. Think about which piece of info should belong to which table. This is of utmost importance to produce predictable numbers.

 

Here's an excerpt from an article by Alberto Ferrari:

 

The golden rule of data modeling is always the same: always use star schemas. If a column has to be used to slice and dice, then it needs to belong to a dimension. Numbers to aggregate, on the other hand, are stored in fact tables. Tabular lets a developer deviate from the regular star schema architecture. This does not mean that doing it is always a good idea. It seldom is.

 

And please remember forever: NEVER JOIN 2 FACT TABLES DIRECTLY.

 

Best

D