Specifying and Querying Database Repairs using Logic Programs with Exceptions
نویسندگان
چکیده
Databases may be inconsistent with respect to a given set of integrity constraints. Nevertheless, most of the data may be consistent. In this paper we show how to specify consistent data and how to query a relational database in such a way that only consistent data is retrieved. The speciication and queries are based on disjunctive extended logic programs with positive and negative exceptions that generalize those previously introduced by Kowalski and Sadri.
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