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Abstract
In this work, we described the database models, Relational database Model, Object Oriented Database Model and Object Relational Database model. In a wide view, we studied the basic concepts and formalizations of the Object Oriented Database model, then described the famous methodologies.
We introduce a review of the definitions of hypermedia and hypertext as well as the difference between them and multimedia. Also the basic concepts of hypermedia system and techniques relevant to the field of hypermedia. Also we illustrated the famous hypermedia design model that is the Object Oriented Hypermedia Design Model.
Finally, this thesis presented an object oriented hypermedia database for building an online magazine, which is treated as an enhanced hypermedia application. The main contributions are a direct result of taking advantage of the combination of hypermedia modeling and object oriented database management systems.
Among the main results we can cite:
The Unified Modeling Language UML is used to represent the model as it is now the standard language for modeling OO systems. The Class Diagram is used to represent the several classes in the model, as well as, the relationships between them. The functionality of the system is shown as a list of Use Cases and a subset of the Use Case diagram is presented. Moreover, example scenarios are illustrated to show how to implement these use cases.
The mapping defined in this research has been targeted to utilize most of the object features within the underlying DBMS. In particular:
Object types support the creation of abstract data types that correspond to class definitions in UML and to other, user-defined complex types that are needed for attribute definitions.
Object tables are created from object types and used to hold persistent instances with object identifiers that correspond to UML class objects.
Embedded objects are used to define complex attribute value from user defined object types.
Object references (REFs) are used to define relationships between objects.
Object types hierarchies are used to define inheritance relationship.
VARRAYS and nested tables are used to implement multivalued attributes and multivalued relationships between objects.
Triggers are used to maintain inverse relationships between objects
Indeed, the Interactive Online Magazine provides a framework for creating, storing, processing and organizing complex hypermedia application. Furthermore, complex queries can be submitted to hypermedia data supplied by the Interactive Online Magazine.