Today, XML is primarily regarded as a syntax for exchanging structured data, and therefore the question of how to develop well-designed XML models (in the sense of abstract descriptions of XML-based data models) has not been studied extensively. However, since applications are increasingly penetrated by XML technologies (Web Services), and because query and programming languages increasingly provide native XML support (XQuery and E4X), it would be beneficial to use these features to work together with well-designed XML models. In order to better focus on XML-oriented technologies in systems engineering and programming languages, an XML modeling language should be used, which is more focused on modeling and structure than typical XML schema languages, which tend to focus on details of the XML syntax. Currently, there is no well-established XML modeling language, but there are several approaches which could be used as a foundation for XML modeling, the two most important developments being formal models of XML, and ER-inspired conceptual modeling languages for XML. In this talk, we give an overview of existing formal and conceptual models for XML, and present a list of requirements for a language which would be close to the ideal XML modeling language.
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companyis an Unordered Entity (
itemis a Mixed Entity
contactnumis a Generalization