الفهرس | Only 14 pages are availabe for public view |
Abstract The design process is often difficult, time consuming and error prone. Also retrieving the original design of a database (reverse engineering it), is usually a difficult job due to the lack of the original• design documents. Therefore, automating both of these tasks would be of great help. In this thesis we present a tool for automating the design and reverse engineering of relational database systems. We will call this system Designer. The system allows the user to graphically define an Extended Entity-Relationship (EER) model. This model allows additional semantics in comparison to normal entity-relationship model. Namely these are: ternary relationships, generalization and subset hierarchies. It posses powerful graphical editing tools such as: tab control, toolbox, toolbar, DROP down and pop-up menus. It also has the property of zoom in/out and presentation-quality reporting features. entity-relationship model is then decomposed The extended according to a set of basic entity-relationship constructs and then are transformed into candidate relations. These relations are used to physically create a database using ODBC connection or a DDL SQL script is generated to create the database later on the same machine or any other machine. |