【摘要】 <正>一、引言进人九十年代以来,数据库技术和网络技术的飞速发展使信息产业突飞猛进。随着Internet/Int-tranet上的WWW日渐流行,越来越多地出现分布式的、自治的、包括各类数据库、正文、声音、图像、HTML等异构形式的信息源。更多还原

【Abstract】 In this paper,the Open World Assumption is adopted as the fundamental of integration,a data model mixed with object and relation model is given as the foundation of integrated query,then the description form of both contents and query expression are discussed .which will facilitate the expansion of information sources. Finally,a framework based on Mediator and sources description is presented,which will make well use of the description information in individual sources too.更多还原