Principles of database and knowledge-base systems, Vol. I
Principles of database and knowledge-base systems, Vol. I
Consistent query answers in inconsistent databases
PODS '99 Proceedings of the eighteenth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems
On the Desirability of Acyclic Database Schemes
Journal of the ACM (JACM)
Foundations of Databases: The Logical Level
Foundations of Databases: The Logical Level
Elements Of Finite Model Theory (Texts in Theoretical Computer Science. An Eatcs Series)
Elements Of Finite Model Theory (Texts in Theoretical Computer Science. An Eatcs Series)
ConQuer: efficient management of inconsistent databases
Proceedings of the 2005 ACM SIGMOD international conference on Management of data
Data exchange: semantics and query answering
Theoretical Computer Science - Database theory
Theory of Relational Databases
Theory of Relational Databases
Consistent query answering under key and exclusion dependencies: algorithms and experiments
Proceedings of the 14th ACM international conference on Information and knowledge management
Clean Answers over Dirty Databases: A Probabilistic Approach
ICDE '06 Proceedings of the 22nd International Conference on Data Engineering
First-order query rewriting for inconsistent databases
Journal of Computer and System Sciences
Efficient query evaluation on probabilistic databases
The VLDB Journal — The International Journal on Very Large Data Bases
Consistent query answering under primary keys: a characterization of tractable queries
Proceedings of the 12th International Conference on Database Theory
Probabilistic databases: diamonds in the dirt
Communications of the ACM - Barbara Liskov: ACM's A.M. Turing Award Winner
MayBMS: a probabilistic database management system
Proceedings of the 2009 ACM SIGMOD International Conference on Management of data
On the consistent rewriting of conjunctive queries under primary key constraints
Information Systems
Minimal-change integrity maintenance using tuple deletions
Information and Computation
On the consistent rewriting of conjunctive queries under primary key constraints
DBPL'07 Proceedings of the 11th international conference on Database programming languages
On the first-order reducibility of unions of conjunctive queries over inconsistent databases
EDBT'06 Proceedings of the 2006 international conference on Current Trends in Database Technology
Proceedings of the 4th International Workshop on Logic in Databases
On the tractability and intractability of consistent conjunctive query answering
Proceedings of the 2011 Joint EDBT/ICDT Ph.D. Workshop
A dichotomy in the complexity of consistent query answering for queries with two atoms
Information Processing Letters
FQAS'11 Proceedings of the 9th international conference on Flexible Query Answering Systems
Certain conjunctive query answering in first-order logic
ACM Transactions on Database Systems (TODS)
On the data complexity of consistent query answering
Proceedings of the 15th International Conference on Database Theory
Prioritized repairing and consistent query answering in relational databases
Annals of Mathematics and Artificial Intelligence
Certain conjunctive query answering in SQL
SUM'12 Proceedings of the 6th international conference on Scalable Uncertainty Management
Tractable cases of clean query answering under entity resolution via matching dependencies
SUM'12 Proceedings of the 6th international conference on Scalable Uncertainty Management
Query rewriting using datalog for duplicate resolution
Datalog 2.0'12 Proceedings of the Second international conference on Datalog in Academia and Industry
Charting the tractability frontier of certain conjunctive query answering
Proceedings of the 32nd symposium on Principles of database systems
A dichotomy in the complexity of counting database repairs
Journal of Computer and System Sciences
Policy-based inconsistency management in relational databases
International Journal of Approximate Reasoning
Why is it Hard to Obtain a Dichotomy for Consistent Query Answering?
LICS '13 Proceedings of the 2013 28th Annual ACM/IEEE Symposium on Logic in Computer Science
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A natural way for capturing uncertainty in the relational data model is by having relations that violate their primary key constraint, that is, relations in which distinct tuples agree on the primary key. A repair (or possible world) of a database is then obtained by selecting a maximal number of tuples without ever selecting two distinct tuples that have the same primary key value. For a Boolean query q, CERTAINTY(q) is the problem that takes as input a database db and asks whether q evaluates to true on every repair of db. We are interested in determining queries q for which CERTAINTY(q) is first-order expressible (and hence in the low complexity class AC0). For queries q in the class of conjunctive queries without self-join, we provide a necessary syntactic condition for first-order expressibility of CERTAINTY(q). For acyclic queries, this necessary condition is also a sufficient condition. So we obtain a decision procedure for first-order expressibility of CERTAINTY(q) when q is acyclic and without self-join. We also show that if CERTAINTY(q) is first-order expressible, its first-order definition, commonly called (certain) first-order rewriting, can be constructed in a rather straightforward way.