Semistructured and structured data in the Web: going back and forth

Database systems offer efficient and reliable technology to query structured data. However, because of the explosion of the World Wide Web, an increasing amount of information is stored in repositories organized according to less rigid structures, usually as hypertextual documents, and data access is based on browsing and information retrieval techniques. Since browsing and search engines present important limitations, several query languages for the Web have been recently proposed. These approaches are mainly based on a loose notion of structure, and tend to see the Web as a huge collection of unstructured objects, organized as a graph Clearly, traditional database techniques are of little use in this field, and new techniques need to be developed. In this paper, we present the approach to the management of Web data as attacked in the ARANEUS project carried out by the database group at University Roma Tre Our approach is based on a generalization of the notion of view to the Web framework.