I have a fact table that has product keys and product information it also has customer keys with customer information. I want to seperate the fact table into three tables (sales, product and customer). I know how to do this, but need help in the next part which is some of those foreign keys in the fact table have null values or incorrect values and different products have the same incorrect values in some occasions however the product and customer fields have information/values that make them distinct. How can I got about doing this.
P.S.Also a heads up I contacted the I.T. team who said it will be difficult to change at the source as I have had this recommendation before.
