نمودار ERD بیمارستان با مشخصات زیر: 1-The hospital keeps some information about the patient such as : name, age, gender, birthdate and address. 2-The hospital assigns a unique identification number to each patient and also keeps a record for the patient including reception id, reception date and discharge date. 3-The hospital considers a doctor for each patient. Doctor’s information includes: name, id, specialty, work experience (in ages for example 20 ages) and seniority. Each doctor can observe more than one patient. 4-Every patient belongs to one unit of the hospital. Each unit can be known with unit number, unit name and unit type (such as ICU, CCU, etc). Each unit has several hospital beds and each bed has it’s own number and type ( like electrical or simple bed). 5-If a patient needs a surgical operation, the hospital will plan for this. The hospital will provide patients a form for surgical operation including operation number, date, time, patient ...