Entity Relationship Model

Entity relationship model is useful in developing a conceptual design for a database. Creating an entity relationship diagram while designing a database, helps the designer to understand the required components of database and their relationship with each other. So an ER model defines relationships between entities.

An ER diagram helps in expressing the overall logical structure of a database graphically. Its important components are:

1. Entities
2. Attributes
3. Relationships
4. Documenting Entities, Attributes, and Relationships