Results 11 to 20 of about 1,234 (209)
Size Bounds and Algorithms for Conjunctive Regular Path Queries. [PDF]
International Conference on Database Theory, 2023 Conjunctive regular path queries (CRPQs) are one of the core classes of queries over graph databases. They are join intensive, inheriting their structure from the relational setting, but they also allow arbitrary length paths to connect points that are to be joined.
Cucumides, Tamara +2 more
semanticscholar +8 more sources
Answering Regular Path Queries Under Approximate Semantics in Lightweight Description Logics
AAAI Conference on Artificial Intelligence, 2021 Classical regular path queries (RPQs) can be too restrictive for some applications and answering such queries under approximate semantics to relax the query is desirable.
O. Gil, Anni-Yasmin Turhan
semanticscholar +3 more sources
Acyclic Conjunctive Regular Path Queries are no Harder than Corresponding Conjunctive Queries
CoRRWe present an output-sensitive algorithm for evaluating an acyclic Conjunctive Regular Path Query (CRPQ). Its complexity is written in terms of the input size, the output size, and a well-known parameter of the query that is called the "free-connex fractional hypertree width". Our algorithm improves upon the complexity of the recently introduced output-
Mahmoud Abo Khamis +4 more
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Complexity of Conjunctive Regular Path Query Homomorphisms
Conference on Computability in Europe, 2019 15 pages. Short version appeared in the proceedings of the 15th Conference on Computability in Europe (CIE 2019)
Beaudou, Laurent +4 more
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Output-Sensitive Evaluation of Acyclic Conjunctive Regular Path Queries
CoRRConjunctive Regular Path Queries, or CRPQs for short, are an essential construct in graph query languages. In this paper, we propose the first output-sensitive algorithm for evaluating acyclic CRPQs. It is output-sensitive in the sense that its complexity is a function of the sizes of the input graph and of the query output.
Abo Khamis, Mahmoud +5 more
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The First Order Truth behind Undecidability of Regular Path Queries Determinacy [PDF]
International Conference on Database Theory, 2018 In our paper [Gluch, Marcinkowski, Ostropolski-Nalewaja, LICS ACM, 2018] we have solved an old problem stated in [Calvanese, De Giacomo, Lenzerini, Vardi, SPDS ACM, 2000] showing that query determinacy is undecidable for Regular Path Queries.
Grzegorz Gluch +2 more
semanticscholar +2 more sources
Data Path Queries over Embedded Graph Databases
ACM SIGACT-SIGMOD-SIGART Symposium on Principles of Database Systems, 2022 This paper initiates the study of data-path query languages (in particular, regular data path queries (RDPQ) and conjunctive RDPQ (CRDPQ)) in the classic setting of embedded finite model theory, wherein each graph is "embedded" into a background infinite
Diego Figueira, Artur Jeż, A. Lin
semanticscholar +3 more sources
Conjunctive Context-Free Path Queries
International Conference on Database Theory, 2014 In graph query languages, regular expressions are commonly used to specify the labeling of paths. A natural step in increasing the expressive power of these query languages is replacing regular expressions by context-free grammars.
Jelle Hellings
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On the Complexity of Evaluating Regular Path Queries over Linear Existential Rules
International Conference on Web Reasoning and Rule Systems, 2016 International audienceIn the setting of ontology-mediated query answering, a query is evaluated over a knowledge base consisting of a database instance and an ontology.
Meghyn Bienvenu, M. Thomazo
semanticscholar +3 more sources