7 4 Relationships and Entities
From Visual LANSA Logical Modeler
7.4 Relationships and Entities
Relationship rules are defined based on entity type. Remember, entities are defined before relationships. The Logical Modeler only allows meaningful relationships to be defined for a given entity type as the logical model can be built into a physical database. For example, a Parent/Child relationship can be defined only between Data, Variant and External entities.
These are the default relationship rules:
|
Relationship Type |
Source Entity Type |
Target Entity Type |
|
Parent/Child |
Data, Variant or External |
Data |
|
Join |
Data or Variant |
Data, Variant or External |
|
Variation |
Data |
Variant |
|
Include |
Data |
Conceptual |
For more information about how to define Source and Target entities, refer to 7.3 Source and Target Entities and 7.7.1 Create a Relationship.
Also see 7.2 Relationship Rules.
Note: Abstractions are not entities. They are objects used to group entities. Abstraction cannot be used in relationships.