After completing a course in database management, you have been hired as a data analyst by Abdel-Nasser Hospital. Your first assignment is to work as part of a team of three persons to develop a high-level E-R diagram for the hospital. You conduct interviews with a number of hospital administrators and staff to identify the key entities for the hospital. After a short time your team has identified the following entities:
·Ward a treatment center within the hospital. Examples of wards are maternity and emergency care. Each ward has a ward number (identifier) and a ward name.
· Patient a person who is either admitted to the hospital or is registered in an outpatient program. Each patient has a patient number (identifier) and name.
· Physician a member of the hospital medical staff who may admit patients to the hospital and who may administer medical treatments. Each physician has a physician ID (identifier) and name.
·Bed a hospital bed that may be assigned to a patient who is admitted to the hospital. Each bed has a bed number (identifier), a room number, and a ward number.
· Item any medical or surgical item that may be used in treating a patient. Each item has an item number (identifier), description, and unit cost.
· Employee any person employed as part of the hospital staff. Each employee has an employee number and name.
· Treatment any test or procedure performed by a physician on behalf of a patient. Each treatment has a treatment ID that consists of two parts:
treatment number, and treatment name.
The team next recorded the following information concerning relationships:
1. Each hospital employee is assigned to work in one or more wards. Each ward has at least one employee. and may have any number of employees. Th hospital records the number of hours per week t a given employee works in a particular ward.
2. Each ward has exactly one employee who is designated nurse in charge for that ward.
3. A given patient may or may not be assigned to a bed (since some patients are outpatients). Abed may or may not be assigned to a patient.