Originally Posted by
NTC
I will forewarn you that if their points is a single field value, rather than a table, then it can be tricky to reverse should a transaction be cancelled or modified. You are probably best designing 'Points' as one does inventory. In a well designed inventory database there is never a field that holds the stock amount - - rather it is always calculated on-the-fly as the sum of Stock In and Stock Out. Your best approach to points is also a Points In and Points Out approach - as this is more robust which will become evident when changes/reversals/modifications occur to transactions.