Consistent Answers from Integrated Data Sources
نویسندگان
چکیده
When data sources are integrated into a single global system, inconsistencies wrt global integrity constraints are likely to occur. In this paper, the notion of consistent answer to a global query in the context of the local-as-view approach to data integration is characterized. Furthermore, a methodology for generating query plans for retrieving consistent answer to global queries is introduced. For this purpose, an extension of the inverse-rules algorithm for deriving query plans for answering firstorder queries is presented.
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