Scalar aggregation in inconsistent databases

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Scalar aggregation in inconsistent databases

We consider here scalar aggregation queries in databases that may violate a given set of functional dependencies. We define consistent answers to such queries to be greatest lowest/least upper bounds on the value of the scalar function across all (minimal) repairs of the database. We show how to compute such answers. We provide a complete characterization of the computational complexity of this...

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ژورنال

عنوان ژورنال: Theoretical Computer Science

سال: 2003

ISSN: 0304-3975

DOI: 10.1016/s0304-3975(02)00737-5