Web and Document Databases: An Effective Way to Explore the Internet

In this paper, we discuss the architecture of a system, the so-called Web and Document Databases (WDDBS for short), designed to explore the Internet effectively and efficiently. Abstractly, a WDDBS can be defined as a triple, where (1) D stands for a local docu¬ment database to store XML documents, (2) P for a subsystem responsible for remote query evaluation, including resolution of semantic conflicts among heterogeneous databases, and (3) W for a Web crawler which should be able to find information sources related to the local database in some way. Then, each information source can be organized into a WDDB distributed over the Internet, which may be con¬nected to others through URLs. A query submitted to a WDDBS will first be evaluated against the local document database, and then possibly switched over to some remote document databases if necessary, which is controlled by the ‘knowledge’ on how local WDDBSs are connected. In this way, the load of traffic over the Internet can effectively be decreased, but the information explored is more relevant.