A flexible and effective XML storage and retrieval system

As XML becomes increasingly pervasive on the Web, it is necessary to provide a good solution to storing and retrieving huge amount of XML data that includes not only textual data, but also multimedia documents in XML format. Using the Sem-ODB, a multimedia database system, as the underlying repository, we show how the XML storage and retrieval issue can be tackled in a flexible and effective way. We present a prototype that effectively maps and stores XML data into a Sem-ODB through the use of a meta-schema-based approach. Our approach is flexible and effective because (1) users are given control over the resulting mapping scheme via the manipulation of the KnowledgeBase; (2) it greatly reduces the number of joins generated in the final Sem-SQL query when translating an XQuery query.