Each relationship consists of two memberships, one for each participation of an entity type in the relationship.
For an instance, consider a company in which customers place orders. The following illustration is part of an Entity Relationship Diagram showing that customers place orders.
The rectangles represent entity types, and the line between them represents the relationship. The other symbols are introduced in Relationship Cardinality.
The relationship that is shown between CUSTOMER and ORDER consists of two separate relationship memberships:
Each membership has its own set of characteristics. The following illustration depicts the division of this relationship into its two memberships.
Each membership describes an aspect of the entire relationship. The relationship is fully described by the properties of its two relationship memberships.
In CA Gen, each element of a relationship membership definition contributes to building a sentence that describes that membership except for the description.
In addition, some of the definition appears in the graphical representation of the Entity Relationship Diagram.
The details that are captured for each relationship membership include:
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