Combining Heterogeneous Data Sources through Query Correspondence Assertions.

Web Information and Data ManagementPublished 1 January 1998

Ulf Leser

Citations11

TL;DR

This work presents an approach to this problem that is based on a declarative representation of the content of heterogeneous data sources with respect to a global schema, and describes the language to express these correspondences and give the algorithm that uses them to answer global queries.

Abstract

The WWW today offers free access to a wealth of heterogeneous data sources. Combining related data from different sources in a comfortable and automatic fashion is not possible. We present our approach to this problem that is based on a declarative representation of the content of heterogeneous data sources with respect to a global schema. We describe our language to express these correspondences and give the algorithm that uses them to answer global queries. 1.1 Keywords database integration, query translation, mediation 2. INTRODUCTION The recent years have seen a steep increase in the amount of data available for public use, mainly pushed through the success of the World-Wide-Web. However, combining data from different sources to yield more complete answers or to answer more complex queries faces many problems. For instance, the same information is often stored using different structures in different sources. Obtaining the same piece of data from different sources can re...

Keywords

Computer Science

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