Features of the Object-Relational Model

Key Features of the Object-Relational Model
Oracle implements the object-type system as an extension of the relational model. The object-type interface continues to support standard relational database functionality such as queries (SELECT...FROM...WHERE), fast commits, backup and recovery, scalable connectivity, row-level locking, read consistency, partitioned tables, parallel queries, cluster database, export/import, loader, and so forth. But SQL and various programmatic interfaces to Oracle--including PL/SQL, Java, Oracle Call Interface, Pro*C/C++, OO4O--have been enhanced with new extensions to support objects. The result is an object-relational model, which offers the intuitiveness and economy of an object interface while preserving the high concurrency and throughput of a relational database.

Type Inheritance
Type inheritance adds to the usefulness of objects by enabling you to create type hierarchies by defining successive levels of increasingly specialized subtypes that de...