Testing implications of data dependencies
ACM Transactions on Database Systems (TODS)
Complexity and expressive power of logic programming
ACM Computing Surveys (CSUR)
Foundations of Databases: The Logical Level
Foundations of Databases: The Logical Level
The Implication Problem for Data Dependencies
Proceedings of the 8th Colloquium on Automata, Languages and Programming
JELIA '96 Proceedings of the European Workshop on Logics in Artificial Intelligence
Omega-Restricted Logic Programs
LPNMR '01 Proceedings of the 6th International Conference on Logic Programming and Nonmonotonic Reasoning
LPNMR '01 Proceedings of the 6th International Conference on Logic Programming and Nonmonotonic Reasoning
Sesame: A Generic Architecture for Storing and Querying RDF and RDF Schema
ISWC '02 Proceedings of the First International Semantic Web Conference on The Semantic Web
A proposal for an owl rules language
Proceedings of the 13th international conference on World Wide Web
Jena: implementing the semantic web recommendations
Proceedings of the 13th international World Wide Web conference on Alternate track papers & posters
Deciding Regular Grammar Logics with Converse Through First-Order Logic
Journal of Logic, Language and Information
Data exchange: semantics and query answering
Theoretical Computer Science - Database theory
The DLV system for knowledge representation and reasoning
ACM Transactions on Computational Logic (TOCL)
The Description Logic Handbook
The Description Logic Handbook
A Tableau Decision Procedure for $\mathcal{SHOIQ}$
Journal of Automated Reasoning
Tractable Reasoning and Efficient Query Answering in Description Logics: The DL-Lite Family
Journal of Automated Reasoning
Proceedings of the twenty-seventh ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems
Data Complexity of Query Answering in Expressive Description Logics via Tableaux
Journal of Automated Reasoning
Query Answering in the Description Logic Horn-$\mathcal{SHIQ}$
JELIA '08 Proceedings of the 11th European conference on Logics in Artificial Intelligence
Web Semantics: Science, Services and Agents on the World Wide Web
Combining a DL Reasoner and a Rule Engine for Improving Entailment-Based OWL Reasoning
ISWC '08 Proceedings of the 7th International Conference on The Semantic Web
Computable Functions in ASP: Theory and Implementation
ICLP '08 Proceedings of the 24th International Conference on Logic Programming
Implementing an Inference Engine for RDFS/OWL Constructs and User-Defined Rules in Oracle
ICDE '08 Proceedings of the 2008 IEEE 24th International Conference on Data Engineering
Generalized schema-mappings: from termination to tractability
Proceedings of the twenty-eighth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems
Experiences Using Logic Programming in Bioinformatics
ICLP '09 Proceedings of the 25th International Conference on Logic Programming
One More Decidable Class of Finitely Ground Programs
ICLP '09 Proceedings of the 25th International Conference on Logic Programming
Conjunctive query answering for the description logic SHIQ
Journal of Artificial Intelligence Research
Data complexity of reasoning in very expressive description logics
IJCAI'05 Proceedings of the 19th international joint conference on Artificial intelligence
Conjunctive query answering in the description logic EL using a relational database system
IJCAI'09 Proceedings of the 21st international jont conference on Artifical intelligence
On chase termination beyond stratification
Proceedings of the VLDB Endowment
Hypertableau reasoning for description logics
Journal of Artificial Intelligence Research
OWL rules: A proposal and prototype implementation
Web Semantics: Science, Services and Agents on the World Wide Web
GrinGo: a new grounder for answer set programming
LPNMR'07 Proceedings of the 9th international conference on Logic programming and nonmonotonic reasoning
Conjunctive queries for a tractable fragment of OWL 1.1
ISWC'07/ASWC'07 Proceedings of the 6th international The semantic web and 2nd Asian conference on Asian semantic web conference
Query answering under non-guarded rules in datalog+/-
RR'10 Proceedings of the Fourth international conference on Web reasoning and rule systems
Datalog+/-: A Family of Logical Knowledge Representation and Query Languages for New Applications
LICS '10 Proceedings of the 2010 25th Annual IEEE Symposium on Logic in Computer Science
Chase termination: a constraints rewriting approach
Proceedings of the VLDB Endowment
Nominals, inverses, counting, and conjunctive queries or: why infinity is your friend!
Journal of Artificial Intelligence Research
On rules with existential variables: Walking the decidability line
Artificial Intelligence
Towards farsighted dependencies for existential rules
RR'11 Proceedings of the 5th international conference on Web reasoning and rule systems
OWLIM – a pragmatic semantic repository for OWL
WISE'05 Proceedings of the 2005 international conference on Web Information Systems Engineering
Framework for an automated comparison of description logic reasoners
ISWC'06 Proceedings of the 5th international conference on The Semantic Web
Extending decidable existential rules by joining acyclicity and guardedness
IJCAI'11 Proceedings of the Twenty-Second international joint conference on Artificial Intelligence - Volume Volume Two
Query answering in the horn fragments of the description logics SHOIQ and SROIQ
IJCAI'11 Proceedings of the Twenty-Second international joint conference on Artificial Intelligence - Volume Volume Two
The combined approach to ontology-based data access
IJCAI'11 Proceedings of the Twenty-Second international joint conference on Artificial Intelligence - Volume Volume Three
Modelling structured domains using description graphs and logic programming
ESWC'12 Proceedings of the 9th international conference on The Semantic Web: research and applications
Computing stable models for nonmonotonic existential rules
IJCAI'13 Proceedings of the Twenty-Third international joint conference on Artificial Intelligence
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Answering conjunctive queries (CQs) over a set of facts extended with existential rules is a prominent problem in knowledge representation and databases. This problem can be solved using the chase algorithm, which extends the given set of facts with fresh facts in order to satisfy the rules. If the chase terminates, then CQs can be evaluated directly in the resulting set of facts. The chase, however, does not terminate necessarily, and checking whether the chase terminates on a given set of rules and facts is undecidable. Numerous acyclicity notions were proposed as sufficient conditions for chase termination. In this paper, we present two new acyclicity notions called model-faithful acyclicity (MFA) and model-summarising acyclicity (MSA). Furthermore, we investigate the landscape of the known acyclicity notions and establish a complete taxonomy of all notions known to us. Finally, we show that MFA and MSA generalise most of these notions. Existential rules are closely related to the Horn fragments of the OWL 2 ontology language; furthermore, several prominent OWL 2 reasoners implement CQ answering by using the chase to materialise all relevant facts. In order to avoid termination problems, many of these systems handle only the OWL 2 RL profile of OWL 2; furthermore, some systems go beyond OWL 2 RL, but without any termination guarantees. In this paper we also investigate whether various acyclicity notions can provide a principled and practical solution to these problems. On the theoretical side, we show that query answering for acyclic ontologies is of lower complexity than for general ontologies. On the practical side, we show that many of the commonly used OWL 2 ontologies are MSA, and that the number of facts obtained by materialisation is not too large. Our results thus suggest that principled development of materialisation-based OWL 2 reasoners is practically feasible.