Joining fact tables

I have a order fact table. I have a call fact table. For each order, there is a call associated with it. Would I have the call id on the order fact and to join the 2 facts?

Or the order id on the call. Whichever works for you.

Just curious, but why do you need to join the 2 fact tables? If you need to join them on more that a very infrequent basis, why would you simply put which ever dimensions you need on 1 fact table on the other fact table?

I'm assming dellsters is referring to degenerate dimensions. In a sales order model is it very rare you would have or need an Order dimension... same thing with call logs.

Thanks for the information.