36. A computer-usable medium as described in claim 35 wherein a schema is extended from a parent class entity to a child class entity based on used-defined parent-child inheritance relationships.
36. A computer-usable medium as described in claim 35 wherein a schema is extended from a parent class entity to a child class entity based on used-defined parent-child inheritance relationships. 37. A computer-usable medium as described in claim 36 wherein said child class entity inherits relationships from said parent class entity.