VIEW DEFINITION IN AN OBJECT-ORIENTED DATABASE

The paper describes a novel method for creating views in an object-oriented database system by using a mechanism termed 'dynamic instance conversion'. In this system, views are not defined as the result of a query expression but rather by reference to the class of which a view is to be made. It is argued that this approach is better suited to OODBs than the use of query expressions as it is more in keeping with the object-oriented paradigm. Instances of a class are automatically converted between views to appear in the format demanded by a query. This happens without loss of information by the instances, thus ensuring that changes to a view are 'updated' correctly. A Graphical User Interface (GUI) to the view system is also described. This GUI facilitates the creation of views and provides support for the definition of methods used to update view changes.