How to identify entity from a given problem

Entity in DBMS can be a real-world object with an existence. To identify entity from a given problem, follow the below given tips −

Under the problem description, try to find the entity.

• Search for nouns, like Teacher, Doctor, etc.
• Classify nouns to get a wider picture about the entities.
• Read the problem description repeatedly.
• Entities are like Persons, Students, Teachers, Courses.
• Entities has attributes, that properties describing it, for example, for Professor entity, the attributes are  Professor_Name, Professor_Address, Professor_Salary, etc

For example,

Problem Description

Hospital has doctors and patients. Patients visit the hospital to get a consultation from the doctor. Doctor may suggest tests to examine the condition of the patient.

Entities

The following are the entities −

• Hospital
• Patient
• Doctor
• Tests

Attributes

• The attributes for Hospital Entity: Hospital_Name, Hospital_Location, Hospital_Phone, etc.
• The attributes for Patient Entity: Patient_Id, Patient_Name, Patient_Age, Patient_VisitDate, etc.
• The attributes for Doctor Entity: Doctor_Id, Doctor_Name, Doctor_Specialization, etc.
• The attributes for Tests Entity: Tests_Name, Tests_Date, Tests_Result, etc.