Exercise 04
Refunds & Revenue
Finance asks you for net revenue per user. The orders table has every order ever placed. The refunds table records refunds against those orders (an order can be partially or fully refunded; in this dataset, refunds are full).
Tables: orders(id, user_id, amount_cents, ordered_at), refunds(id, order_id, amount_cents, refunded_at).
Return `user_id` and `net_revenue_cents` (orders minus refunds) for every user who has ever placed an order. Include users whose net is zero. Order by `user_id`.