Normalized ER diagram for a restaurant management system covering Customers, Tables, Reservations, Orders, MenuItems, OrderDetails, Staff, and Payments. Customers link to Reservations and Orders, while Staff manages both Tables and order processing through foreign key relationships. OrderDetails bridges Orders to MenuItems with quantity and subtotal tracking, and Payments closes the transaction loop. This schema supports full-service restaurant operations from booking through checkout. Fork this diagram on Diagrams.so to adapt it for your hospitality database project.