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Reference Types

  1. Reference to objects: An attribute of a type can be a reference to an object of a specific type, e.g., ref(Person).
  2. Reference to tuples: Tuples of a table can also have references to them. E.g., ref(people). It can be implemented using the primary key or tuple-id.
  3. SQL-3 uses identity (for tuples) and oid for objects.

Osmar Zaiane
Tue Jul 7 15:03:55 PDT 1998