If you mean just recording the product without the actual price used, that loses information and isn't what I'd do. I would write the price IDs that were used a

If you mean just recording the product without the actual price used, that loses information and isn't what I'd do. I would write the price IDs that were used and input different prices during happy hour. Same complexity as writing the $ amounts except I'm writing fkeys instead so I track which pricing structure was used. If the customer uses a coupon, I relate to it. If I have a distributed system with often-disconnected followers, I sync in new prices and coupons without affecting the old ones. If local managers are allowed to temporarily change prices, I preserve the local price when syncing in the headquarters' price (in fact the local one would probably be in a separate "price overrides" table).