Nice. Ok, one more exercise on NULLIF and we'll go on to another section.
Mr Amund wants to offer a new promotion.
The promotion is as follows: every customer who orders a product and picks it up on their own (i.e., no shipping required) can buy it at a special price: the initial price MINUS the shipping_cost! If the shipping_cost is greater than the price itself, then the customer still pays the difference (i.e. the absolute value of price - shipping_cost).
Our customer has $1,000.00 again and wants to know how many products of each kind they could buy. Show each product name with the column quantity which calculates the number of products. Drop the decimal part. If you get a price of 0.00, show NULL instead.
Use floor(x) to remove the unwanted decimal part. Use abs(x) to get the absolute value.
