Composite Objects
Composite Objects
- Aggregation - grouping parts into a whole
- Attributes -> Objects
- Objects -> Composite objects
- Nesting possible
- Singled out for reasons of convenience
- deletion, copying etc.
- physical clustering
- Usually declared using a keyword in the PL: doc: PARENT Document <-> chaps;
- Additional semantics might have additional keywords
- An object can participate in several aggregation hierarchies...