Updating XML Documents Without Breaking their Validity

Over the past few years, XML has become a standard for data representation and data exchange over the web. Although XML data is self-describing, most application domains tend to use document schemas, given as Document Type Definitions (DTDs) or XML-Schemas. An XML document is considered valid if it conforms to the constraints and rules specified in its schema. A lot of work has been done in querying XML documents. Recently, the issue of updating XML documents has gained attention because an update operation may invalidate the whole document. In this paper, we present existing approaches to update XML documents and offer a new one that guarantees that the updated document still conforms to its DTD. Our methodology updates XML documents without breaking their validity by storing and retrieving XML documents in/from an object database.