Querying Inconsistent Databases

Distance-Based Repairs of Databases

“…It is easy to verify that d u and d u , Σ corresponds to the repair method introduced in [1], which inspires many other works on (domain independent) database repair (see, e.g., [2,4,6,7,22,21,28]). It is also interesting to check the distance-based functions of Definition 7 when the domain independent d u is taken as the basic distance function.…”

“…. , n. In an attempt to overcome this problem, most of the existing algorithms for query answering do not compute the repairs themselves, but make inferences using rewriting techniques [1], logic programming paradigms [2,16,19,21,22], (hyper-)graph computations [10,11], and proof theoretic methods, such as analytic tableaux [7]. Tractability in such cases is usually reached only for restricted syntactical forms of the integrity constraints.…”

On the Computational Complexity of Minimal-Change Integrity Maintenance in Relational Databases

“…In the framework of Arenas, Bertossi and Chomicki [4], which was adapted by the follow-up papers [5,6,7,8,9,11,12,19,21,25,26,34,41,45,46,49,62], the smallest unit to be deleted from (or added to) a database in the process of repairing is a tuple. A different choice is made by Wijsen [64] where tuples themselves are being repaired.…”

“…Representing repairs as answer sets of logic programs with disjunction and classical negation has been proposed in a number of papers [5,7,12,34,45,46,49,62]. Those papers consider computing consistent answers to first-order queries.…”

“…The problem of computing consistent query answers is the second computational problem studied in the present paper. The notion of consistent query answer proposed by Arenas, Bertossi and Chomicki [4] has been used and extended in many papers [5,6,7,8,9,11,12,16,19,20,21,25,26,27,34,41,45,46,49,62,64]. This research has been surveyed by Bertossi and Chomicki [13].…”