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Extending inclusion dependencies with conditions

Shuai Ma, Wenfei Fan, Loreto Bravo
2014 Theoretical Computer Science  
i.e., there exists a sound and complete inference system for the implication analysis of CINDs; and (c) the implication problem for CINDs has the same complexity as its traditional counterpart, namely  ...  PSPACE-complete and coNP-complete, respectively; and (f) the implication problem for acyclic unary CINDs remains in PTIME in the absence of finite-domain attributes and coNP-complete in the general setting  ...  sound and complete  ... 
doi:10.1016/j.tcs.2013.11.002 fatcat:uehu37dqrfad5isic27jbw23qy

Data exchange with arithmetic operations

Balder ten Cate, Phokion G. Kolaitis, Walied Othman
2013 Proceedings of the 16th International Conference on Extending Database Technology - EDBT '13  
We show that, for arithmetic schema mappings without target dependencies, the existence-of-solutions problem can be solved in polynomial time, and, if a solution exists, then a universal solution (suitably  ...  We initiate the study of data exchange for arithmetic schema mappings, that is, schema mappings specified by source-totarget dependencies and target dependencies that may include arithmetic formulas interpreted  ...  We thank Nimrod Megiddo and Marcus Schaefer for helpful discussions and pointers. References  ... 
doi:10.1145/2452376.2452439 dblp:conf/edbt/CateKO13 fatcat:rt5ah3lhrbfylonbwhjcupjsfm

Inclusion Dependencies in XML: Extending Relational Semantics [chapter]

Michael Karlinger, Millist Vincent, Michael Schrefl
2009 Lecture Notes in Computer Science  
be sound and complete.  ...  We also investigate the implication problem for XINDs in complete XML documents, a class of XML documents that generalizes the notion of a complete relation, and present an axiom system that we show to  ...  We present an axiom system for XIND implication and show that the system is sound and complete.  ... 
doi:10.1007/978-3-642-03573-9_3 fatcat:wkqwqsnyinhcthx5xr3z52anai

The LLUNATIC data-cleaning framework

Floris Geerts, Giansalvatore Mecca, Paolo Papotti, Donatello Santoro
2013 Proceedings of the VLDB Endowment  
In this paper we develop a uniform framework to solve this problem. We propose a new semantics for repairs, and a chase-based algorithm to compute minimal solutions.  ...  As a consequence, there is currently no general algorithm to solve database repairing problems that involve different kinds of constraints and different strategies to select preferred values.  ...  Rep Rep f,f = 25K → {t4.SALARY, We next show that the chase procedure always generates solutions, i.e., it is sound, and it terminates after a finite number of steps.  ... 
doi:10.14778/2536360.2536363 fatcat:q7bg5zqnizdrbonmo5bj6dtzra

Automatic schema merging using mapping constraints among incomplete sources

Xiang Li, Christoph Quix, David Kensche, Sandra Geisler
2010 Proceedings of the 19th ACM international conference on Information and knowledge management - CIKM '10  
In this paper, we present a novel approach for merging multiple relational data sources related by a collection of mapping constraints in the form of P2P style tuple-generating dependencies (tgds).  ...  In the scenario of data integration, we opt for minimal mediated schemas that are complete regarding certain answers of conjunctive queries.  ...  Acknowledgements: The authors are grateful to the anonymous referees for comments helping to improve the paper.  ... 
doi:10.1145/1871437.1871479 dblp:conf/cikm/LiQKG10 fatcat:kn2vw6ryaveb7fh3f3ozvvcrtu

Updates of Relational Views

Stavros S. Cosmadakis, Christos H. Papadimitriou
1984 Journal of the ACM  
The problem of translating the insertion of a tuple into a view is then studied in detail, and the results are extended to the cases of deletion and replacement of a tuple.  ...  Projective views of databases that consist of a single relation and satisfy funcuonal dependencies are emphasized.  ...  Recall that the chase procedure consists in repeatedly locating a pair of tuples ~, v such that ~[Z] ~-v[Z] and ~[A] # viA] for some FD Z ---, A in 2;, and replacing the element t,[A] with viA] throughout  ... 
doi:10.1145/1634.1887 fatcat:alyfg7vatfff3e26fxu75bxvxy

Conceptual Graph Rules and Equivalent Rules: A Synthesis [chapter]

Marie-Laure Mugnier
2009 Lecture Notes in Computer Science  
We focus here on conceptual graph rules and on the semantically equivalent knowledge constructs in logic and databases, namely rules with existential variables and tuple-generating dependencies.  ...  The aim of this presentation is to synthesize main decidability, complexity and algorithmic results obtained on this kind of rules.  ...  A ∀∃-rule has the same form as a very general kind of dependency studied in databases called tuple-generating dependency (TGD) [AHV95] .  ... 
doi:10.1007/978-3-642-03079-6_3 fatcat:4y4ybhv4t5hzrcz7ankvxrz37y

Query Processing in Data Integration

Paolo Guagliardo, Piotr Wieczorek, Marc Herbstritt
2013 Dagstuhl Publications  
A rewriting Q r ∈ L r of a query Q ∈ L q under sound views V is L r -maximal iff, there is no rewriting Q r ∈ L r of Q under V such that, for some V-extension E which is sound w.r.t. some database D, it  ...  The first part of the chapter focuses on the problem of query answering in the relational setting, and describes approaches based on variants of the chase, along with how to deal with integrity constraints  ...  Hence, if CQ were complete for CQ-to-CQ rewritings, we would immediately have a decision procedure also for the determinacy for CQ queries and views.  ... 
doi:10.4230/dfu.vol5.10452.129 dblp:conf/dagstuhl/GuagliardoW13 fatcat:2bqbnhu3wbe3rcvsck6aqzr3em

Data exchange

Ronald Fagin, Phokion G. Kolaitis, Lucian Popa
2003 Proceedings of the twenty-second ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems - PODS '03  
A universal solution has homomorphisms into every possible solution, and hence is a "most general possible" solution. Nonetheless, given a source instance, there may be many universal solutions.  ...  Earlier results imply that this problem is both NP-hard and coNP-hard. Here, we pinpoint its exact complexity by establishing that it is a DP-complete problem.  ...  Miller, Arnon Rosenthal, Wang-Chiew Tan, Val Tannen, and Moshe Y. Vardi for helpful suggestions, comments, and pointers to the literature.  ... 
doi:10.1145/773153.773163 dblp:conf/pods/FaginKP03 fatcat:pygtrcoiojf63nknc6ainn23my

Data exchange: getting to the core

Ronald Fagin, Phokion G. Kolaitis, Lucian Popa
2005 ACM Transactions on Database Systems  
A universal solution has homomorphisms into every possible solution, and hence is a "most general possible" solution. Nonetheless, given a source instance, there may be many universal solutions.  ...  Earlier results imply that this problem is both NP-hard and coNP-hard. Here, we pinpoint its exact complexity by establishing that it is a DP-complete problem.  ...  Miller, Arnon Rosenthal, Wang-Chiew Tan, Val Tannen, and Moshe Y. Vardi for helpful suggestions, comments, and pointers to the literature.  ... 
doi:10.1145/1061318.1061323 fatcat:usqqjntxzvddzipuwcxgnzbhve

Ontological Multidimensional Data Models and Contextual Data Qality [article]

Leopoldo Bertossi, Mostafa Milani
2017 arXiv   pre-print
At the core of a multidimensional context we include a generalized multidimensional data model and a Datalog+/- ontology with provably good properties in terms of query answering.  ...  Data quality assessment and data cleaning are context-dependent activities.  ...  It includes a set of validity constraints for contexts, a model theory, as well as a set of sound and complete inference rules. D.  ... 
arXiv:1704.00115v2 fatcat:r2e6asojkvenlcfvtlj4tz62ja

Schema mappings, data exchange, and metadata management

Phokion G. Kolaitis
2005 Proceedings of the twenty-fourth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems - PODS '05  
In addition, we highlight some research issues and directions for future work. * On leave from UC Santa Cruz.  ...  Our main aim in this paper is to present an overview of recent advances in data exchange and metadata management, where the schema mappings are between relational schemas.  ...  I am grateful to Ronald Fagin for reading earlier versions of this paper and offering numerous valuable comments, corrections, and suggestions for improvement.  ... 
doi:10.1145/1065167.1065176 dblp:conf/pods/Kolaitis05 fatcat:a7u5jmcoubggxpfitbwd4zmf4u

Inconsistency-Tolerant Reasoning in Datalog $$^{\pm }$$ ± Ontologies via an Argumentative Semantics [chapter]

Maria Vanina Martinez, Cristhian Ariel David Deagustini, Marcelo A. Falappa, Guillermo Ricardo Simari
2014 Lecture Notes in Computer Science  
Here we introduce elements of defeasible argumentative reasoning in Datalog ± , consequences to represent statements whose truth can be challenged leading to a better handling of inconsistency in ontological  ...  The Semantic Web provides an effective infrastructure that allows data to be easily shared and reused across applications.  ...  This work was partially supported by CONICET Argentina, SeGCyT Universidad Nacional del Sur in Bahia Blanca, UK Engineering and Physical Sciences Research Council (EPSRC) grant EP/J008346/1 (PrOQAW).  ... 
doi:10.1007/978-3-319-12027-0_2 fatcat:pfqyogwygrbylhgsyh63djtmji

Functional and inclusion dependencies a graph theoretic approach

Stavros S. Cosmadakis, Paris C. Kanellakis
1984 Proceedings of the 3rd ACM SIGACT-SIGMOD symposium on Principles of database systems - PODS '84  
WC prcscnt a nrw graph thcorctic approach to t!ic implication problem for functional (l:D) and inclusion (IND) dcpcndcncics.  ...  WC provide new lower bounds for the implication of typed. acyclic IND's and FD's -NP-hardness and PSPAtXhardncss for bounded domains. Finally.  ...  Acknonlcdgcments: We would like to thank Moshc Vardi for many helpful discussions.  ... 
doi:10.1145/588011.588016 dblp:conf/pods/CosmadakisK84 fatcat:mklbgivhpbfv7idfnxxqmnks2u

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

Arash Karimi, Heng Zhang, Jia-Huai You
2020 arXiv   pre-print
The chase procedure for existential rules is an indispensable tool for several database applications, where its termination guarantees the decidability of these tasks.  ...  More generally, we show that the approach can be applied to the hierarchy of bounded rule sets previously only defined for the skolem chase.  ...  Furthermore, if R consists of rules with singlehead, then MembCheck(R, δ) is sound and complete.  ... 
arXiv:2005.05423v1 fatcat:3xebbndxknbfzb7uz4cmcx7nq4
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