A system for querying disparate, heterogeneous data sources over a network, where at least some of the data sources are World Wide Web pages or other semi-structured data sources, includes a query converter, a command transmitter, and a data retriever. The query converter produces, from at least a portion...http://www.google.com.tw/patents/US6282537?utm_source=gb-gplus-share專利 US6282537 - Query and retrieving semi-structured data from heterogeneous sources by translating structured queries
