Object Oriented XML Query by Example

This paper describes an XML query language called XML-QBE, which can be used to both query and update XML documents and databases. The language itself has a simple XML form, and uses a query by example paradigm. This language was designed as a middleware layer between UML data models and backend database schemas, as part of a solution to the distributed, heterogeneous data-base problem and legacy database problem. Because the XML layer is derived from UML, XML-QBE is object-oriented. Queries and updates have a very similar form, and the form itself is XML. Therefore this language is also easy to process and analyze. We describe the language, the rationale, and our solution architecture.