Star schema [fact 1:n dimension]…how?

Question

I am a newcomer to data warehouses and have what I hope is an easy question about building a star schema:

If I have a fact table where a fact record naturally has a

Answer 1

You should load a fact record for each promotion, even if the dollar amount is the same. If in fact, each type of promotion in your example is truly represented by this specific dollar amount, then a fact record should be loaded with the key of the promotion type, also containing keys back to other related dimensions (including Date).

The main point here is don't worry about data duplication. Think about a sales-oriented Data Warehouse, for say, a fast food company. One can assume there won't be just one fact record for $4.13, which is used to represent a million distinct sales of "value meal #3". Instead, each record in the "Transaction" dimension would have a relationship with at least one specific fact record in this hypothetical Sales fact table.