Entity Relationship Diagram, Essay Example

An entity-relationship diagram (ERD), also known as an entity-relationship model, is a graphical representation that depicts relationships among people, objects, places, concepts, or events within an information technology (IT) system.

Healthcare Database

The above Entity Relation Diagram describes how patient data is related to the reminder data. In the patient entity, it contains the Name, Address, and email of the patient. The email attribute would contain the primary key because every patient contains a specific email and cannot share the email. In the reminder entity, it contains the Reminder ID, Subject, and Body. The Reminder ID attribute contains the primary key because the IDs are not the same for different patients. In the relationship between the patient entity and the reminder, a one-to-many entity relationship is where one patient can receive numerous reminders. In the relationship between reminders and patient entity is that one to one relationship where one reminder can be sent to one patient.