Plymouth Car Rental (PCR) started in with two compact cars and has expanded its fleet
of vehicles with several sedans and trucks. When a customer books a rental, his/her age
has to be at least 18 for compact cars and sedans, which are rented by the day and must
be returned the following morning by 11 AM. Trucks are rented for a maximum of six
hours. The owner requires a deposit on the reservation to be paid within seven days of
booking. Vehicle records consist of the makes and types (Honda sedan), color, seating
capacity, required deposit, rental rate and rental limit (in hours). Customer data consists
of customer’s names, addresses, phone numbers, and birth dates. Bookings identify the
customer, vehicle, as well as the time rented and returned. There can be several
payments up until the reservation date. Payments must reflect the payment status for
each booking, including deposit, when the deposit was made, then each of the payments
made, and when the entire payment was completed.
In addition, PCR decided to reward their customers who refer other customers with gas
coupons on their future rentals (which also servers the purpose of retaining those
customers). Because the business is booming, PCR added several other vehicles, both
trucks and sedans and wants to expand information gathered on these. In particular,
PCR wants to track several truck-related attributes such as towing capacity and whether
it has a snow plow or not. For the sedans, geared towards nature explorers, it wants to
track the type and capacity of bike racks, and whether it has a canoe rack.
For questions 82 – 86, please refer to the preceding paragraph.
Describe the nature of recursive relationship in this case (if any) and discuss how it
would be modeled in the ER diagram for this database.