On the Computational Complexity of Consistent Query Answers
<|reference_start|>On the Computational Complexity of Consistent Query Answers: We consider here the problem of obtaining reliable, consistent information from inconsistent databases -- databases that do not have to satisfy given integrity constraints. We use the notion of consistent query answer -- a query answer which is true in every (minimal) repair of the database. We provide a complete classification of the computational complexity of consistent answers to first-order queries w.r.t. functional dependencies and denial constraints. We show how the complexity depends on the {\em type} of the constraints considered, their {\em number}, and the {\em size} of the query. We obtain several new PTIME cases, using new algorithms.<|reference_end|>
@article{chomicki2002on,
    title={On the Computational Complexity of Consistent Query Answers},
    author={Jan Chomicki, Jerzy Marcinkowski},
    journal={arXiv preprint arXiv:cs/0204010},
    year={2002},
    archivePrefix={arXiv},
    eprint={cs/0204010},
    primaryClass={cs.DB}
}