The database schema consists of several tables including Availability, Suburb, Dish, and Order. The Availability table tracks the availability of drivers for delivery purposes. The Suburb table contains information about the suburb where the driver delivers orders. The Dish table has details about individual dishes such as name, description, preparation type, main ingredients, course type, E-F rating, carbon cost, price, delivery time, and restaurant ID. The Order table tracks order information including customer ID, date of order, expected delivery time, actual delivery time, current status, and ordered dish.