An object relational database for hypermedia systems

interface design Abstract interface objects, responses to external events, interface transformations Abstract data views configuration diagrams ADV-charts design patterns Mapping between navigation and perceptible objects. Composition and generalization/ specialization Model perceptible objects, implementing chosen metaphors, describe interface for navigational objects define lay-out of interface objects implementation Running application Those supported by the target environment Those provided by the target environment Performance completeness F.M. Ghaleb et al. / Hypermedia systems 358 Alexandria Engineering Journal, Vol. 43, No. 3, May 2004 This paper is concerned with the conceptual design and the navigational design of a hypermedia system. The model is presented using UML and the implementation of this model is using ORACLE8i. 3. Database modeling in UML Conceptual modeling is an important phase in designing a successful database application. The Entity-Relationship ER model is a popular high-level conceptual data model. This model and its variations are frequently used for the conceptual design of "traditional" database applications. Object modeling methodologies, such as UML (Unified Modeling Language) and OMT (Object Modeling Technique) are becoming increasingly popular. Although these methodologies were developed mainly for software design, a major part of software design involves designing the database that will be accessed by the software modules. Hence, an important part of these methodologies-namely, the class diagrams are similar to ER diagrams in many ways. The UML distinguishes between the notions of diagram and model. A model contains all of the underlying elements of information about a system under consideration and does so independent of how these elements are usually presented. A diagram is a particular visualization of certain kinds of elements from the model and generally exposes only a subset of these elements detailed information. A given model element might exist on multiple diagrams, but there is one definition of that element in the underlying model. The notation and semantics for the following kinds of diagrams are supported in UML: