5 tables in my (simplyfied) model :

PRODUCT
prod_id
descr

PRODUCT_SUPPLIER
prod_id (related to PRODUCT.prod_id)
supp_id (related to SUPPLIER.supp_id)
purch_price

SUPPLIER
supp_id
name

PURCH_ORDER
order_no
supp_id (related to SUPPLIER.supp_id)

PURCH_ORDER_DETAIL
pk
order_no (related to PURCH_ORDER.order_no)
prod_id (related to PRODUCT.prod_id)
qty

To calculate order totals I need to get from the order detail to product supplier, and when doing this in crystal reports, it says that having "differents paths pointing to the same table and this is generally not supported" and I don't get correct results. What is wrong with this approach ?