Normalization of XML Schema Definitions

Abstract

An XML schema definition can be organized according to one of the following design styles: "Russian Doll", "Salami Slice", "Venetian Blind", or "Garden of Eden"; otherwise, it is said to be in "Bologna" style, which actually means free format. Converting a complex XML schema from a style to another without automated support is not a trivial task. The "Garden of Eden" style can be considered as a normalized format since the definitions of all components (i.e., elements, attributes and types) are global and, thus, can be re-used in the definition of other XML schema constructs (e.g., when expanding the schema or importing it into another schema or using it to define an XML namespace). In this work, we present a Normalize procedure, which can be used to convert any given XML schema to the "Garden of Eden" style, by automatically transforming and rearranging all declarations and definitions it contains.