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Chasing Streams with Existential Rules [article]

Jacopo Urbani, Markus Krötzsch, Thomas Eiter
2022 arXiv   pre-print
For that, we show how to translate LARS with existentials into a semantics-preserving set of existential rules.  ...  To bridge this gap, we extend LARS, a well-known framework for rule-based stream reasoning, to support existential rules.  ...  The authors would like to thank Mike Spadaru for his work on earlier versions of the prototype used in this work.  ... 
arXiv:2205.02220v1 fatcat:fzeipn243bblrplwuzzwsfcno4

Optimizing the chase

George Konstantinidis, José Luis Ambite
2014 Proceedings of the VLDB Endowment  
In both these problems we make use of the chase algorithm, the main tool to reason with dependencies.  ...  Our second contribution is to use the frugal chase to scale up query answering using views under LAV weakly acyclic target constraints, a useful language capturing RDF/S.  ...  The Chase is useful to reason with dependencies.  ... 
doi:10.14778/2733085.2733093 fatcat:rngrlclvbnfcppsbcnpdkqle4a

Existential Rule Languages with Finite Chase: Complexity and Expressiveness

Heng Zhang, Yan Zhang, Jia-Huai You
2015 PROCEEDINGS OF THE THIRTIETH AAAI CONFERENCE ON ARTIFICIAL INTELLIGENCE AND THE TWENTY-EIGHTH INNOVATIVE APPLICATIONS OF ARTIFICIAL INTELLIGENCE CONFERENCE  
Finite chase, or alternatively chase termination, is an important condition to ensure the decidability of existential rule languages.  ...  In the past few years, a number of rule languages with finite chase have been studied. In this work, we propose a novel approach for classifying the rule languages with finite chase.  ...  Under an existential rule language, queries are answered against a logical theory consisting of an input database and a finite set of existential rules, while a chase procedure is usually used.  ... 
doi:10.1609/aaai.v29i1.9404 fatcat:xk73pcgiqzcajoguyr3q6ov7om

The Power of the Terminating Chase (Invited Talk)

Markus Krötzsch, Maximilian Marx, Sebastian Rudolph, Michael Wagner
2019 International Conference on Database Theory  
In this invited tutorial, we therefore ask about the expressive power of logical theories for which the chase terminates.  ...  A "Datalog-first" standard chase that prioritises applications of rules without existential quantifiers makes modelling simpler -and we conjecture: computationally more efficient.  ...  Acknowledgements We thank David Carral for his comments on an earlier version of this paper.  ... 
doi:10.4230/lipics.icdt.2019.3 dblp:conf/icdt/KrotzschMR19 fatcat:t63tgjkpynffxpq366j4wiaiky

Existential Rule Languages with Finite Chase: Complexity and Expressiveness [article]

Heng Zhang, Yan Zhang, Jia-Huai You
2015 arXiv   pre-print
Finite chase, or alternatively chase termination, is an important condition to ensure the decidability of existential rule languages.  ...  In the past few years, a number of rule languages with finite chase have been studied. In this work, we propose a novel approach for classifying the rule languages with finite chase.  ...  Here we only explain how to define the linear order. Let us first consider the case where k is even. The general idea is to construct a sequence of rule sets (Σ i ) i≥0 .  ... 
arXiv:1411.5220v3 fatcat:aenn7e4f5jbxpj47kjt6irouyq

The chase revisited

Alin Deutsch, Alan Nash, Jeff Remmel
2008 Proceedings of the twenty-seventh ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems - PODS '08  
We show that the standard chase is incomplete for finding universal model sets, and we introduce the extended core chase which is complete, i.e. finds an F -universal model set when it exists.  ...  By choosing F appropriately, we extend prior results all the way to existential first-order queries and ∀∃-first-order constraints (and various standard sublanguages).  ...  We generalize Proposition 2, showing how to use F -universal model sets to check containment under constraints for expressive query and constraint languages. THEOREM 10.  ... 
doi:10.1145/1376916.1376938 dblp:conf/pods/DeutschNR08 fatcat:kf557cnz4vaqzfrjtc4ttphizy

Chase Termination for Guarded Existential Rules

Marco Calautti, Georg Gottlob, Andreas Pieris
2015 Proceedings of the 34th ACM Symposium on Principles of Database Systems - PODS '15  
One of the central problems regarding the chase procedure is all-instance termination, that is, given a set of tuple-generating dependencies (TGDs) (a.k.a. existential rules), decide whether the chase  ...  under that set terminates, for every input database.  ...  Let us first consider the less expressive classes.  ... 
doi:10.1145/2745754.2745773 dblp:conf/pods/CalauttiGP15 fatcat:zeenwrnwpjan7n2oqlp2sjslza

Diagram Chase in Relational System Development

Michael Ebert, Georg Struth
2005 Electronical Notes in Theoretical Computer Science  
This makes the approach particularly suitable for mechanization and automation. Its usefulness for visual reasoning is illustrated by various examples.  ...  These are similar to those for functional diagrams in category theory and inspired by rewriting theory.  ...  Acknowledgment: The authors would like to thank the anonymous referees and the participants of the VLFM'04 for valuable discussions.  ... 
doi:10.1016/j.entcs.2004.08.049 fatcat:gwar6lxgabhinar2m2yq3zgmla

Benchmarking the Chase

Michael Benedikt, George Konstantinidis, Giansalvatore Mecca, Boris Motik, Paolo Papotti, Donatello Santoro, Efthymia Tsamoura
2017 Proceedings of the 36th ACM SIGMOD-SIGACT-SIGAI Symposium on Principles of Database Systems - PODS '17  
and a set of test scenarios-for evaluating chase implementations across a wide range of assumptions about the dependencies and the data.  ...  We used our benchmark to compare chase-based systems on data exchange and query answering tasks with one another, as well as with systems that can solve similar tasks developed in closely related communities  ...  INTRODUCTION The chase [25] is a long-standing technique developed by the database community for reasoning with constraints expressed as a certain kind of logical formulas.  ... 
doi:10.1145/3034786.3034796 dblp:conf/pods/BenediktKMMPST17 fatcat:yausei2vbrakfnktmxmoho7dme

Distribution Constraints: The Chase for Distributed Data

Gaetano Geck, Frank Neven, Thomas Schwentick, Jean Christoph Jung, Carsten Lutz
2020 International Conference on Database Theory  
This paper introduces a declarative framework to specify and reason about distributions of data over computing nodes in a distributed setting.  ...  In particular, they can express co-partitioning constraints and constraints about range-based data distributions by using comparison atoms.  ...  These verifying computations all assume the same set Z. We use a kind of timestamps to avoid cyclic reasoning. The details of this proof are given in the full version.  ... 
doi:10.4230/lipics.icdt.2020.13 dblp:conf/icdt/GeckNS20 fatcat:pi4yzfez2nbdlfl6u7s5iuhbsy

On the Chase for All Provenance Paths with Existential Rules [chapter]

Abdelraouf Hecham, Pierre Bisquert, Madalina Croitoru
2017 Lecture Notes in Computer Science  
In this paper we focus on the problem of how lineage for existential rules knowledge bases.  ...  We build upon the notion of Graph of Atoms Dependency (GAD) and use it to solve the problem of provenance path loss in the context of forward chaining with existential rules.  ...  In this paper we studied the problem of generating all minimal provenance paths for an atomic ground query in the context of a knowledge base expressed using existential rules.  ... 
doi:10.1007/978-3-319-61252-2_10 fatcat:yeubdgbgjbg73fj3lq3xmbbekq

Distribution Constraints: The Chase for Distributed Data [article]

Gaetano Geck, Frank Neven, Thomas Schwentick
2020 arXiv   pre-print
This paper introduces a declarative framework to specify and reason about distributions of data over computing nodes in a distributed setting.  ...  In particular, they can express co-partitioning constraints and constraints about range-based data distributions by using comparison atoms.  ...  Reasoning We consider the implication problem for distribution constraints in Section 4.1, and adapt the chase to degds and data-full dtgds in Section 4.2, as a means to solve it.  ... 
arXiv:2003.00965v1 fatcat:qdiyqrxtc5ctbcx5ht2gqxgr4q

Restricted Chase Termination for Existential Rules: a Hierarchical Approach and Experimentation [article]

Arash Karimi, Heng Zhang, Jia-Huai You
2020 arXiv   pre-print
More generally, we show that the approach can be applied to the hierarchy of bounded rule sets previously only defined for the skolem chase.  ...  The chase procedure for existential rules is an indispensable tool for several database applications, where its termination guarantees the decidability of these tasks.  ...  Definition 9 Let ∆ denote an arbitrary acyclicity condition of finite skolem chase (for convenience, let us also useto denote the class of rule sets that satisfy the acyclicity condition expressed by  ... 
arXiv:2005.05423v1 fatcat:3xebbndxknbfzb7uz4cmcx7nq4

Oblivious Chase Termination: The Sticky Case

Marco Calautti, Andreas Pieris, Michael Wagner
2019 International Conference on Database Theory  
On rules with existential variables: Walking the decidability line. Artif. Intell., 175(9-10):1620-1654, 2011. 3 Catriel Beeri and Moshe Y. Vardi. A proof procedure for data dependencies.  ...  For brevity, we write σ as φ(x,ȳ) → ∃z ψ(x,z), and use comma instead of ∧ for joining atoms. We refer to φ(x,ȳ) and ψ(x,z) as the body and head of σ, denoted body(σ) and head(σ), respectively.  ...  Let us explain the reason.  ... 
doi:10.4230/lipics.icdt.2019.17 dblp:conf/icdt/CalauttiP19 fatcat:cokafs6trbehfma273b4bgzw2i

Taming the Infinite Chase: Query Answering under Expressive Relational Constraints

A. Calì, G. Gottlob, M. Kifer
2013 The Journal of Artificial Intelligence Research  
For these classes, the chase procedure is not guaranteed to terminate and thus may have an infinite outcome.  ...  This paper introduces expressive classes of TGDs defined via syntactic restrictions: guarded TGDs (GTGDs) and weakly guarded sets of TGDs (WGTGDs).  ...  It is now straightforward to see how the initialization rules can be written.  ... 
doi:10.1613/jair.3873 fatcat:lyniplyrmjg75jgz47ddbgbf2e
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