An Entity-Relationship Model, or ER Model, is a conceptual representation of data that typically evolves through three stages: conceptual, logical, and physical.
The associations between entities, such as a Customer "places" an Order . Modelling Business Information: Entity relation...
Defines the numerical context of relationships, such as One-to-One (1:1), One-to-Many (1:N), or Many-to-Many (M:N). The Three Levels of Data Modelling An Entity-Relationship Model, or ER Model, is a
Defines the high-level business scope and key concepts, focusing on business vocabulary rather than technical detail. An Entity-Relationship Model