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Heuristics-based query optimisation for SPARQL

Petros Tsialiamanis, Lefteris Sidirourgos, Irini Fundulaki, Vassilis Christophides, Peter Boncz
2012 Proceedings of the 15th International Conference on Extending Database Technology - EDBT '12  
In this paper we describe a set of useful heuristics for SPARQL query optimizers.  ...  For this reason, the use of good heuristics is essential in SPARQL query optimization, even in the case that are partially used with cost-based statistics (i.e., hybrid query optimization).  ...  These heuristics are generic and can be used separately or complementary to each other, and also in traditional cost-based optimisers to create a hybrid planner. • We propose the first heuristics-based  ... 
doi:10.1145/2247596.2247635 dblp:conf/edbt/TsialiamanisSFCB12 fatcat:onpf27gmvndabivryphmeczcse

On the formulation of performant SPARQL queries

Antonis Loizou, Renzo Angles, Paul Groth
2015 Journal of Web Semantics  
It describes 5 heuristics that can be applied to create optimised queries.  ...  The heuristics are informed by formal results in the literature on the semantics and complexity of evaluating SPARQL queries, which ensures that queries following these rules can be optimised effectively  ...  [39] proposed a set of useful heuristics for SPARQL query optimisers.  ... 
doi:10.1016/j.websem.2014.11.003 fatcat:lb55lstdbjfmvcrf2bqb4lcr5q

On the Formulation of Performant SPARQL Queries

Antonis Loizou, Renzo Angles, Paul Thomas Groth
2015 Social Science Research Network  
It describes 5 heuristics that can be applied to create optimised queries.  ...  The heuristics are informed by formal results in the literature on the semantics and complexity of evaluating SPARQL queries, which ensures that queries following these rules can be optimised effectively  ...  [39] proposed a set of useful heuristics for SPARQL query optimisers.  ... 
doi:10.2139/ssrn.3199178 fatcat:22upsfwqufabrevgcwn3azbtr4

Optimising XML–RDF Data Integration [chapter]

Stefan Bischof
2012 Lecture Notes in Computer Science  
The query language XSPARQL, which is built by combining XQuery and SPARQL, addresses some of these problems.  ...  Establishing an integrated formal model for a core fragment of XSPARQL will allow us to improve performance of query answering by defining query equivalences.  ...  The optimisation heuristics can also be used for related approaches since the model works on the data models of XML and RDF. A cost model will be created, enabling cost based optimisations as well.  ... 
doi:10.1007/978-3-642-30284-8_67 fatcat:drft3r727fhjziow6gyso3ktfa

Some Thoughts on OWL-Empowered SPARQL Query Optimization [chapter]

Vassilis Papakonstantinou, Giorgos Flouris, Irini Fundulaki, Andrey Gubichev
2016 Lecture Notes in Computer Science  
The discovery of optimal or close to optimal query plans for SPARQL queries is a difficult and challenging problem for query optimisers of RDF engines.  ...  Despite the growing volume of work on optimising SPARQL query answering, using heuristics or data statistics (such as cardinality estimations) there is little effort on the use of OWL constructs for query  ...  ., based on statistics) for query planning, and is most appropriate for datasets and benchmarks that use a rich schema structure (e.g., UOBM).  ... 
doi:10.1007/978-3-319-47602-5_3 fatcat:iw3m6enjnrh7liv67g5xvolkhq

Optimisation Techniques for Flexible SPARQL queries

Riccardo Frosini, Alexandra Poulovassilis, Peter T. Wood, Andrea Calì
2022 ACM Transactions on the Web  
RDF datasets can be queried using the SPARQL language but are often irregularly structured and incomplete, which may make precise query formulation hard for users.  ...  performance penalties for fast queries.  ...  ACKNOWLEDGMENTS The authors would like to thank the reviewers for their insightful comments which helped to improve the paper.  ... 
doi:10.1145/3532855 fatcat:bmpxueetprggrier5h5lkmxxla

LHD: Optimising Linked Data Query Processing Using Parallelisation

Xin Wang, Thanassis Tiropanis, Hugh C. Davis
2013 The Web Conference  
We propose LHD, a distributed SPARQL engine that is built on a highly parallel infrastructure and able to minimise query response time, and we evaluate its performance using a BSBM based environment.  ...  The high data traffic cost and response time significantly affect the performance of distributed SPARQL queries as the number of SPARQL end point and the volume of data at each endpoint increase.  ...  The significant optimisation time on complex queries does not occur in LHD as a result of using heuristics in the optimisation algorithm.  ... 
dblp:conf/www/WangTD13 fatcat:vhbguup7m5avxarh5oe3nljq3i

Optimising Linked Data Queries in the Presence of Co-reference [chapter]

Xin Wang, Thanassis Tiropanis, Hugh C. Davis
2014 Lecture Notes in Computer Science  
In this environment we demonstrate the advantages of LHD-d for distributed SPARQL queries in environments with co-reference.  ...  with co-reference into a normal query with pre-existing bindings; 2) an algorithm named Ψ , that intensively exploits parallelism, and dynamically optimises queries using runtime statistics.  ...  Based on the aforementioned methods, we implement a dis-tributed SPARQL engine, named LHD-d 4 that is able to process co-referential queries with improved efficiency.  ... 
doi:10.1007/978-3-319-07443-6_30 fatcat:sicnqsdvbrhfhnblqebax5hara

Optimization of Different Queries using Optimization Algorithm (DE)

Sahil Saharan, J.S. Lather, R. Radhakrishnan
2018 International Journal of Computer Network and Information Security  
But, still there are some other challenges, like as optimization of the query. We introduce a new approach for real-time SPARQL query optimization with different forms and different triple patterns.  ...  The experimental study focus on main-memory model of RDF data and ARQ query engine of Jena.  ...  Meimaris and Papastefanatos [34] presented a new approach of join reordering that converts a query into a multidimensional vector space and performs distance-based optimisation.  ... 
doi:10.5815/ijcnis.2018.03.06 fatcat:h4jizd5uxza6tfn7d7aikw3xju

Querying a Messy Web of Data with Avalanche

Cosmin Basca, Abraham Bernstein
2014 Social Science Research Network  
Specifically, Avalanche finds up-to-date answers to queries over SPARQL endpoints. It first gets on-line statistical information about potential data sources and their data distribution.  ...  Specifically, Avalanche finds up-to-date answers to queries over SPARQL endpoints. It first gets on-line statistical information about potential data sources and their data distribution.  ...  We are also grateful to the anonymous reviewers for their constructive comments, which helped to substantially improve the paper.  ... 
doi:10.2139/ssrn.3199098 fatcat:dmdm72isgjasvhloa3vcbvjysy

Towards a Scalable and Optimised Context Broker for Seamless Interoperability within IoT Systems

C.B. Tokpo Ovengalt, K. Djouani, A.M. Kurien, A. Chibani
2016 Procedia Computer Science  
Several context brokers have been proposed but they do not offer a scalable and optimised brokering algorithm.  ...  For that, some optimisation methods could be explored to ensure that queries are treated in minimum computational time.  ...  Event Processing (EP) SPARQL 7 is an extension of the SPARQL Protocol and RDF Query Language (SPARQL) on top of which new binary operators such as SEQ, EQUALS, OPTIONALSEQ, and EQUALSOPTIONAL are added  ... 
doi:10.1016/j.procs.2016.08.016 fatcat:r5mfwxyayrdsviv5mutkdyurzi

Implementation of federated query processing on Linked Data

Yuchao Zhou, Suparna De, Klaus Moessner
2013 2013 IEEE 24th Annual International Symposium on Personal, Indoor, and Mobile Radio Communications (PIMRC)  
In this paper, we provide a mechanism for federated querying based on subject and sameAs grouping techniques.  ...  As the number of Linked Data sets increases with more and more interconnections defined between them, querying a single data set is no longer enough for users who need data from mixed domains.  ...  ACKNOWLEDGMENT The authors would like to thank Olaf Görlitz and Andreas Schwarte for their valuable support.  ... 
doi:10.1109/pimrc.2013.6666765 dblp:conf/pimrc/ZhouDM13 fatcat:wjsru4y3r5b63nqbhaxhjxte44

A Native and Adaptive Approach for Unified Processing of Linked Streams and Linked Data [chapter]

Danh Le-Phuoc, Minh Dao-Tran, Josiane Xavier Parreira, Manfred Hauswirth
2011 Lecture Notes in Computer Science  
During query execution, it continuously reorders operators according to some heuristics to achieve improved query execution in terms of delay and complexity.  ...  To remedy these drawbacks, we present CQELS (Continuous Query Evaluation over Linked Streams), a native and adaptive query processor for unified query processing over Linked Stream Data and Linked Data  ...  To allow adaptive query execution, our engine currently support a "cardinality-based" routing policy, based on some heuristics.  ... 
doi:10.1007/978-3-642-25073-6_24 fatcat:aigyxefq6zhcbkxhru3srp7m5u

Reasoning over SPARQL

Sam Coppens, Miel Vander Sande, Ruben Verborgh, Erik Mannens, Rik Van de Walle
2013 The Web Conference  
However, in this case the sparql endpoint provider decides which inference rules are used for its entailment regimes.  ...  Until now, the sparql query language was restricted to simple entailment. Now sparql is being extended with more expressive entailment regimes. This allows to query over inferred, implicit knowledge.  ...  (IWT), the Fund for Scientific Research-Flanders (FWO-Flanders), and the European Union.  ... 
dblp:conf/www/CoppensSVMW13 fatcat:eflaavyt4ncatcxjlk7mpqxcfu

A Hybrid Approach to Linked Data Query Processing with Time Constraints

Steven J. Lynden, Isao Kojima, Akiyoshi Matono, Akihito Nakamura, Makoto Yui
2013 The Web Conference  
In this paper we present a hybrid approach to answering SPARQL queries that makes use of both link traversal-based and distributed query processing-based approaches in order to combine query answering  ...  It is demonstrated how, using a set of heuristics and optimisation techniques, this can be effective when answering queries with time constraints (incomplete answers are acceptable in order to minimise  ...  plan optimisation difficult.  ... 
dblp:conf/www/LyndenKMNY13 fatcat:gj2tydw2vvbf7ax2f5fq4rsuby
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