Information Integration and the Semantic Web

Abstract

Introduction Information integration and interoperability among information sources are related problems that have received significant attention since early days of computer information processing. Initially, for a few decades, the focus was on integration/interoperability for a relatively small number of sources. This is the setting encountered in traditional business and service applications, for example when two companies merge or several services interoperate (which requires the integration of their information systems). Much of the work in this context of federated or multi-databases focused on integrating schemas by defining a global schema in an expressive data model and defining mappings from local schemas to the global one [19]. More recently, in the context of integration of data sources on the internet, the so-called global-as-view (GAV) and local-as-view (LAV) paradigms have emerged out of projects such as TSIMMIS [20] and Information Manifold (IM) [12]. Recently, the a