STAFF is any person employed in the airline company. Each STAFF has a StaffID (identifier), SName, and Contact. The types of STAFF are: PLANE_CREW and OFFICER only. Moreover, PLANE_CREW trained to do their job on air, in the airplane. So, an OFFICER staff cannot do the job of a PLANE_CREW staff. PLANE_CREW is a STAFF in the company. Role needs to be recorded for each PLANE_CREW. OFFICER is another STAFF in the company. An OFFICER has a JobTitle attribute. DEPARTMENT is a department in the company. Each DEPARTMENT has a DeptID (Identifier), a DName, and a Location. FLIGHT Each FLIGHT has a FlightID (Identifier), Departure, Arrival, Duration (which is computed based on the Departure and Arrival), and WeekDay (a flight can go in more than one day per week) attributes. TICKET is issued to a flight. Each TICKET has TicketID (Identifier), and Fare (which is composed of Adult, and Child) . A TICKET cannot exist without a FLIGHT. So, a TICKET depends on a FLIGHT. PASSENGER is a passenger of a certain flight. The attributes of PASSENGER are: PID (Identifier), PName, Mobile, Email, and Age. There are different types of PASSENGERS. Some of them are AGENCY_PASSENEGRs and NON_AGENCY_ PASSENEGRs. Each passenger has the option to book for a flight through an a gency or not. So, an AGENCY_PASSENEGR can become NON_AGENCY_ PASSENEGR and vice versa. Charges is an information to be stored for AGENCY_PASSENEGRs and Savings is to be recoreded for NON_AGENCY_ PASSENEGRs. ROUTE Each ROUTE has a RouteID (Identifier), and Distance AIRPORT is an airport that manages flights. Attributes of AIRPORT are: APCode (Identifier), APName, Country, and City..