Kimball Forum
Would you like to react to this message? Create an account in a few clicks or log in to continue.

Single fact table vs multiple fact tables - what is the right way in a dimensional model?

2 posters

Go down

Single fact table vs multiple fact tables - what is the right way in a dimensional model? Empty Single fact table vs multiple fact tables - what is the right way in a dimensional model?

Post  rafi asraf Thu Jan 24, 2013 8:19 am

Hi

Had a discussion yesterday around wheater dimensional modeling á lá Ralph Kimball is about having star schema only in the sense that each model must only have one fact table, or can we put multiple fact tables, with diffrent grain regaring the same business process, utilizing some of the same dimensions?

I mostly worked with MS cubes, so the risk of end users joining a fact table on the wrong grain was never a problem, as the cube definition solevs this problem. but now I work for a company that will utilized both cubes and relational based data marts.

Appriciate your input.

Regards
Rafi Asraf

rafi asraf

Posts : 5
Join date : 2012-04-17

Back to top Go down

Single fact table vs multiple fact tables - what is the right way in a dimensional model? Empty Re: Single fact table vs multiple fact tables - what is the right way in a dimensional model?

Post  ngalemmo Thu Jan 24, 2013 8:53 pm

rafi asraf wrote:Had a discussion yesterday around wheater dimensional modeling á lá Ralph Kimball is about having star schema only in the sense that each model must only have one fact table, or can we put multiple fact tables, with diffrent grain regaring the same business process, utilizing some of the same dimensions?

Well, yes. A 'star schema' by definition is a single fact table and its dimensions. But, a dimensional data warehouse is a collection of star schema sharing common (conformed) dimensions. This creates an environment that allows modular expansion of the scope of the data warehouse by adding new facts and occasionally new dimensions as needed.
ngalemmo
ngalemmo

Posts : 3000
Join date : 2009-05-15
Location : Los Angeles

http://aginity.com

Back to top Go down

Back to top

- Similar topics

 
Permissions in this forum:
You cannot reply to topics in this forum