From Conjunctive Queries to Instance Queries in Ontology-Mediated Querying

@inproceedings{Feier2018FromCQ,
  title={From Conjunctive Queries to Instance Queries in Ontology-Mediated Querying},
  author={Cristina Feier and Carsten Lutz and Frank Wolter},
  booktitle={IJCAI},
  year={2018}
}
We consider ontology-mediated queries (OMQs) based on expressive description logics of the ALC family and (unions) of conjunctive queries, studying the rewritability into OMQs based on instance queries (IQs). Our results include exact characterizations of when such a rewriting is possible and tight complexity bounds for deciding rewritability. We also give a tight complexity bound for the related problem of deciding whether a given MMSNP sentence (in other words: the complement of a monadic… 
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References

SHOWING 1-10 OF 43 REFERENCES
Conjunctive Query Answering for the Description Logic SHIQ
TLDR
This paper considers conjunctive queries over knowledge bases formulated in the popular DL SHIQ and allows transitive roles in both the query and the knowledge base and shows that query answering is decidable and establishes the following complexity bounds: regarding combined complexity, a deterministic algorithm for query answering that needs time single exponential and double exponential in the size of the query.
Conjunctive Query Answering in the Description Logic EL Using a Relational Database System
TLDR
A novel approach to CQ answering that enables the use of standard relational database systems as the basis for query execution is proposed.
Query and Predicate Emptiness in Ontology-Based Data Access
TLDR
This paper determines the computational complexity of query emptiness and predicate emptiness in the EL, DL-Lite, and ALC-families of description logics, investigates the connection to ontology modules, and performs a practical case study to evaluate the new reasoning services.
Containment in Monadic Disjunctive Datalog, MMSNP, and Expressive Description Logics
TLDR
This work proves 2NExpTime-completeness and extends this result to monadic disjunctive Datalog and to ontology-mediated queries based on expressive description logics and unions of conjunctive queries.
Ontology-Mediated Query Answering with Data-Tractable Description Logics
TLDR
A brief introduction to ontology-mediated query answering using description logic (DL) ontologies, with a focus on DLs for which query answering scales polynomially in the size of the data, as these are best suited for applications requiring large amounts of data.
Query Answering via Modal Definability with FaCT++: First Blood
TLDR
An optimised algorithm for the reduction, its implementation using FaCT++ as an underlying reasoner and the results of first experiments are presented, showing this reduction to work for conjunctive queries without cycles that only involve bound variables.
Tractable query answering and rewriting under description logic constraints
Modal Logic Applied to Query Answering and the Case for Variable Modalities
  • Evgeny Zolin
  • Computer Science, Philosophy
    Description Logics
  • 2007
We present a query answering technique based on notions and results from modal Correspondence Theory. It allows us to answer a wide family of conjunctive queries by polynomial reduction to knowledge…
Pay-as-you-go Ontology Query Answering Using a Datalog Reasoner
TLDR
Although the main goal is to efficiently answer queries over OWL 2 ontologies and data, the technical results are very general and the approach is applicable to first-order knowledge representation languages that can be captured by rules allowing for existential quantification and disjunction in the head.
Conjunctive query answering in the description logic SH using knots
...
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2
3
4
5
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