Views for simplifying access to heterogeneous XML data. CoopIS

Abstract. We present XyView, a practical solution for fast development of user- (web forms) and machine-oriented applications (web services) over a repository of heterogeneous schema-free XML documents. XyView provides the means to view such a repository as an array, queried using a QBE-like interface or through simple selection/projection queries. Close to the concept of universal relation, it extends it in mainly two ways: (i) the input is not a relational schema but a potentially large set of XML data guides; (ii) the view is not defined explicitly by a query but implicitly by various mappings so as to avoid data loss and duplicates generated by joins. Developed on top of the Xyleme content management system, XyView can easily be adapted to any system supporting XQuery.