XML Documents Normalization Using GN-DTD

Designing a well-structured XML document is important for the sake of readability, maintainability and more importantly to avoid both data redundancies and update anomalies. This paper proposes to improve and simplify XML structural design using a normalization process. To achieve this, Graphical Notation for Document Type Definition (GN-DTD) is used to describe the structure of XML document at the schema level. Multiple levels of normal forms for GN-DTD are proposed and the corresponding normalization rules to transform from poorly designed into well-designed XML documents. A case study is presented to show the application of these normal forms and normalization algorithm