The Entity Relationship model, which describes data in terms of entities, attributes, and relations, was introduced by Peter Pin Shan Chen in 1976. At the same time, he proposed a method of diagramming called Entity Relationship (E/R) diagrams, which has become widely accepted. E/R diagrams use rectangles to describe entities, ellipses for attributes, and diamonds to represent relationships.
E/R diagrams use rectangles to describe entities, ellipses for attributes, and diamonds to represent relationships.
