PPT Slide
Structured types and references
- Named types with attributes, O-O subtyping model
- Ref(T) for directly modelling relationships
Typed tables and table hierarchies
- Oid (user-provided) plus a column per attribute of T
- Subtables for querying and managing subtype instances
Query language extensions
- Substitutability for queries/updates (data independence ++)
- Path expressions for querying relationships easily
- Functions/predicates for runtime type inquiries
Object views (via a novel approach)
- Virtual table hierarchies for flexible access control
- Also facilitates O-O views of legacy tables
New O-R Features in DB2 UDB V5.2