Extending a relational DBMS to support complex objects

The definition and manipulation of complex objects in an extended relational database management system are discussed. Complex object types are defined as relation domains encapsulated within methods written in LISP or C. Objects are structured using the set, array and list constructors concepts. Structured objects are manipulated using built-in functions. For a given application, the database administrator introduces the complex domains with the encapsulating methods within the DBMS meta-base using a specific command. Complex domains can be described using an hierarchy which makes possible the inheritance of methods along domains. The domain methods are directly used in the external data manipulation language, which is an extended version of SQL with object-oriented features. Graphical interface procedures are available to input and display nonstandard data. A fully running version of the system is commercially available for Sun Unix workstations. Only the list constructor is available in the current version.<
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