XML: Current Developments and Future Challenges for the Database Community

While we can take as a fact "the Web changes everything", we argue that "XML is the means" for such a change to make a significant step forward. We therefore regard XML-related research as the most promising and challenging direction for the community of database researchers. In this paper, we approach XML-related research by taking three progressive perspectives.We first consider XML as a data representation standard (in the small), then as a data interchange standard (in the large), and finally as a basis for building a new repository technology. After a broad and necessarily coarse-grain analysis, we turn our focus to three specific research projects which are currently ongoing at the Politecnico di Milano, concerned with XML query languages, with active document management, and with XML-based specifications of Web sites.