A Classi cation of Multi Database Languages
نویسندگان
چکیده
This paper de nes a formal classi cation of multi database languages into ve levels of database integration with increasing degree of global control and decreasing degree of local autonomy First the fundamental interoperability concepts and mechanisms are identi ed for each of these levels Their consequences on local autonomy as well as implementation draw backs are discussed Second various multi database languages are classi ed into these categories In addition to our own language COOL other proposals are analyzed including SQL Net Multibase Superviews VODAK Pegasus and O SQL
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