The customer interacts with generally one waiterand places their order, while the waiter takes multiple customers in a day. The customer placesan order with the waiter, the waiter generates an invoice with the details of the customer, theirorder and table number, which is sent to the kitchen. Once the order is prepared the runneruses the invoice to serve the food. The waiter usually asks again if the customers want to orderanything more, this process can go on till the customer decides he does not want any morefood. All the invoices generated by the customer are part of a much larger entity called order.The order is essentially the bill generated in the end by the restaurant for the customer. Nowwe know the customer, waiter and invoice will be present in the order table. Therelationship between customer and order is one to one. The relationship between the waiterand order is one to many. the relationship between invoice and order is one to many.Note: FYI, the relationship between order and invoice can be considered as one to many.