A Web database application model for software maintenance

Web database application programs may consist of hundreds of files. The interoperations among these files could be complex, and most of them are lack of design documents. When a programmer maintains (changes) some programs of an application, the program files affected by the changes need be updated simultaneously to keep the functional consistency. One major difficulty of maintenance is how to identify these affected parts, especially in Web database applications. In this paper, we present a model, called HED model, for the maintenance of Web database applications. HED model decomposes a Web database application into three diagrams, hyperlink diagrams, entity-relationship diagrams, and data-flow diagrams, which are used to represent different aspects of a Web database application. Based on the HED model, the programs files affected by a program change can be identified precisely via the structure and database analyses. In addition, a maintenance tool is implemented to demonstrate the capability of the HED model.