1

The problem

I am trying to make a star schema of the following situation, concerning transactions on a stock market. I have summarized the scenario here:

  • Each transaction traded on the market has
    • 1 or more buyers, which can either be a person or a venue
    • 1 or more sellers, which can either be a person or a venue

ER

The attempt

I have tried looking up best practices on modelling many to many relationships and inheritance in a star schema, and combined these. This gives me the following star schema

Type       Name                   Description
Fact       Transaction            Fact containing all transaction details
Dim        EntityGroup            Groupings of entities (just there to make a complete model - no attributes)
Dim        Entity                 Superclass of all entities (just there to make a complete model - no attributes)
Bridge     EntityGroup_Entity     Bridge for the many-to-many relationship between entities and groups
Dim        Person                 Subclass of entities, holding all attributes of persons (shares the primary key with Dim Entity)
Dim        Venue                  Subclass of entities, holding all attributes of venues 

Star schema

The question

Am i right that this would be best practice for a star schema, or can you point out any places the design is faulty?

0

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.