Data Modeling using ERD We want to realize a database for hotel management. The database must allow the management of several hotels.  Each hotel is described by: number, name, address, and telephone.  Those hotels are divided into different classes. Each class is described by the number of stars and the description. Each hotel contains several rooms. A room is characterized by: number, price per night, and telephone.   However, each room in a hotel belongs to a category. A category is described by: code and description (example: single, double...).  We also wish to register the information of the clients who want to book rooms. A client is characterized by: number, name, first name, date of birth, nationality, and email. A client can make one or more room reservations. Each reservation concerns only one room and one client. A reservation is characterized by: number, start date of residence, and duration (number of nights).   We must have a trace of the reservation modality. A reservation can be done in two ways either online, by completing a reservation form, or at an agency where the client fills a reservation file.  Also we must register the information about the services (breakfast, lunch, dinner ...) ordered during the residence of a client: service number, description, date of service, and price.  During the residence, a client can order zero or more services. A service can be ordered by zero or more clients. Design a representation of the data in terms of entities, attributes and relationships between entities. Construct an ERD diagram to depict this representation. Show the cardinalities using (min, max) or CHEN notation and all necessary information.

Data Modeling using ERD

We want to realize a database for hotel management. The database must allow the management of several hotels. 

• Each hotel is described by: number, name, address, and telephone. 
• Those hotels are divided into different classes. Each class is described by the number of stars and the description.
• Each hotel contains several rooms. A room is characterized by: number, price per night, and telephone.  
• However, each room in a hotel belongs to a category. A category is described by: code and description (example: single, double...). 
• We also wish to register the information of the clients who want to book rooms. A client is characterized by: number, name, first name, date of birth, nationality, and email.
• A client can make one or more room reservations. Each reservation concerns only one room and one client. A reservation is characterized by: number, start date of residence, and duration (number of nights).  
• We must have a trace of the reservation modality. A reservation can be done in two ways either online, by completing a reservation form, or at an agency where the client fills a reservation file. 
• Also we must register the information about the services (breakfast, lunch, dinner ...) ordered during the residence of a client: service number, description, date of service, and price. 
• During the residence, a client can order zero or more services. A service can be ordered by zero or more clients.

Design a representation of the data in terms of entities, attributes and relationships between entities. Construct an ERD diagram to depict this representation. Show the cardinalities using (min, max) or CHEN notation and all necessary information.