POSC Meta Model Specifications Version 2.3 |
Logical Data Model |
This entity defines the subtype/supertype associations between entities. Querying SUB for all instances with a given value of ORIGIN will return all the direct and indirect subtypes of the ORIGIN. Querying ORIGIN for all instances with a given value of SUB will return all the direct and indirect supertypes of SUB. Querying SUPER for a SUB gives all direct supertypes. Querying SUB for a SUPER gives all direct subtypes.
- origin (M: entity_def)
- ORIGIN is either the direct or indirect supertype of SUB.
- source (M: source)
- The source of this association.
- sub (M: entity_def)
- SUB is a direct subtype of SUPER and an indirect subtype of ORIGIN.
- super (M: entity_def)
- SUPER is the direct supertype of SUB.
Local rules:
- Different Related Instance
-
An entity can be a supertype of itself. An entity cannot be a subtype of itself.
- Different Related Instance
-
An entity cannot be an indirect supertype of itself.
Entity projects as table SUPERSUB.
Referenced in Diagrams:
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