Building an inventory system. I have lots of products and each product has three different variables. So for stock totals I want to group by the two columns (product & size) and sum quantity to get stock total.
product | Size | Quantity |
---|---|---|
Widget one | 2 | 275 |
Widget one | 2 | 100 |
Widget two | 3 | 150 |
Widget two | 2 | 150 |