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arXiv · 2207.09198

Consistent Query Answering for Expressive Constraints under Tuple-Deletion Semantics

Lorenzo Marconi·Riccardo Rosati
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Abstract

We study consistent query answering in relational databases. We consider an expressive class of schema constraints that generalizes both tuple-generating dependencies and equality-generating dependencies. We establish the complexity of consistent query answering and repair checking under tuple-deletion semantics for different fragments of the above constraint language. In particular, we identify new subclasses of constraints in which the above problems are tractable or even first-order rewritable.

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Lorenzo Marconi, Riccardo Rosati. 2022-07-19. Consistent Query Answering for Expressive Constraints under Tuple-Deletion Semantics. https://arxiv.org/abs/2207.09198

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