The following tables form part of a database held in a relational DBMS:

Hotel (hotelNo, hotelName, city)

Room (roomNo, hotelNo, type, price)

Booking (hotelNo, guestNo, dateFrom, dateTo, roomNo)

Guest (guestNo, guestName, guestAddress)

Where:

Hotel contains hotel details, and hotelNo is the primary key

Room contains room details for each hotel, and (roomNo, hoteINo) forms the primary key

Booking contains details of bookings, and (hoteINo, guestNo, dateFrom) forms the primary key

Guest contains guest details, and guestNo is the primary key

a) Identify the foreign keys in this schema.

b) Explain how the entity and referential integrity rules apply to these relations.

c) Suggest some general constraints that would be appropriate for this schema.