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Combining Vertex-Centric Graph Processing with SPARQL for Large-Scale RDF Data Analytics

Ibrahim Abdelaziz, Razen Harbi, Semih Salihoglu, Panos Kalnis
2017 IEEE Transactions on Parallel and Distributed Systems  
For complex analytical tasks that combine generic graph processing with SPARQL, Spartex is at least an order of magnitude faster than existing alternatives.  ...  It implements a generic SPARQL operator as a vertex-centric program that interprets SPARQL queries and executes them efficiently using a built-in optimizer.  ...  By coupling our SPARQL operator with a cost-based optimizer, complex SPARQL queries are evaluated efficiently.  ... 
doi:10.1109/tpds.2017.2720174 fatcat:yolgu6hg75fixgtffmmew57kle

Optimizing Analytical Queries over Semantic Web Sources [article]

Dilshod Ibragimov
2017 PhD series, Technical Faculty of IT and Design, ˜Aalborg=ålborgœ University  
In this thesis, we concentrated on optimizing the performance of analytical SPARQL queries.  ...  Chapter 5: Optimizing Aggregate SPARQL Queries Using Materialized RDF Views Naturally, SPARQL endpoints are publicly available and allow the execution of the queries of any complexity.  ... 
doi:10.5278/ fatcat:5d2lmnicazgmze2qhe5cikowwm

Robust Runtime Optimization and Skew-Resistant Execution of Analytical SPARQL Queries on Pig [chapter]

Spyros Kotoulas, Jacopo Urbani, Peter Boncz, Peter Mika
2012 Lecture Notes in Computer Science  
We evaluate the effectiveness of our approach both on a synthetic benchmark known to generate complex queries (BSBM-BI) as well as on a Yahoo!  ...  We describe a system that incrementally translates SPARQL queries to Pig Latin and executes them on a Hadoop cluster.  ...  The choice for this benchmark is based on the scope of this work, namely complex SPARQL queries from an analytical RDF workload.  ... 
doi:10.1007/978-3-642-35176-1_16 fatcat:bkrhd4o36jfnnnm7iuiebaqtm4

SOFOS: Demonstrating the Challenges of Materialized View Selection on Knowledge Graphs [article]

Georgia Troullinou, Haridimos Kondylakis, Matteo Lissandrini, Davide Mottin
2021 arXiv   pre-print
Analytical queries over RDF data are becoming prominent as a result of the proliferation of knowledge graphs.  ...  A well known technique to improve the performance of analytical queries is to exploit materialized views.  ...  The MARVEL system [8] , belonging to this line of work, implements view materialization for optimizing query answering of OLAP SPARQL queries [4] .  ... 
arXiv:2103.06531v1 fatcat:a5frlwq6ezhqxbp5npth7lydeu

Predicting SPARQL Query Performance and Explaining Linked Data [chapter]

Rakebul Hasan
2014 Lecture Notes in Computer Science  
As the complexity of the Semantic Web increases, efficient ways to query the Semantic Web data is becoming increasingly important.  ...  In this paper, firstly we address the problem of SPARQL query performance prediction. Secondly we discuss how to explain Linked Data in a decentralized fashion.  ...  Analytical cost models are unable to capture the complexities of modern database systems [2] .  ... 
doi:10.1007/978-3-319-07443-6_53 fatcat:h7xxf6wr4bfcjmysyiruee22im

Benchmarking Commercial RDF Stores with Publications Office Dataset [chapter]

Ghislain Auguste Atemezing, Florence Amardeilh
2018 Lecture Notes in Computer Science  
This paper presents a benchmark of RDF stores with realworld datasets and queries from the EU Publications Office (PO).  ...  , stability and query execution.  ...  Fig. 1 . 1 BGP repartition of SPARQL queries in Category 1. Table 1 . 1 BGP repartition of SPARQL queries in Category 2.  ... 
doi:10.1007/978-3-319-98192-5_54 fatcat:aeux3zbbuncgfa33kbnsfkaiv4

Ephedra: Efficiently Combining RDF Data and Services Using SPARQL Federation [chapter]

Andriy Nikolov, Peter Haase, Johannes Trame, Artem Kozlov
2017 Communications in Computer and Information Science  
Ephedra provides a flexible declarative mechanism for including hybrid services into a SPARQL federation and implements a number of static and runtime query optimization techniques for improving the hybrid  ...  SPARQL queries performance.  ...  Specialized SPARQL federation engines focus on optimal processing of distributed SPARQL queries.  ... 
doi:10.1007/978-3-319-69548-8_17 fatcat:4xbpne6mwndyfilcranyllp2im

Efficient Parallel Processing of Analytical Queries on Linked Data [chapter]

Stefan Hagedorn, Kai-Uwe Sattler
2013 Lecture Notes in Computer Science  
RDF and SPARQL have been established as de-facto standards for representing and querying linked data and there exists quite a number of RDF stores and SPARQL engines that can be used to work with the data  ...  However, for many types of queries on linked data these stores are not the best choice regarding query execution times.  ...  Analytical queries also have to filter for entities within ranges of complex types like location or time. To test the support for this kind of queries, a benchmark must provide appropriate queries.  ... 
doi:10.1007/978-3-642-41030-7_33 fatcat:6xelv336lbgnfjmq7a4ltt3bnq

The Query Translation Landscape: a Survey [article]

Mohamed Nadjib Mami, Damien Graux, Harsh Thakkar, Simon Scerri, Sören Auer, Jens Lehmann
2019 arXiv   pre-print
Both industry and research communities have been keen to develop such techniques, which require the translation of a chosen 'universal' query language to the various data model specific query languages  ...  The lack of data interoperability limits the potential of its collective use for novel applications.  ...  Within a single match()-step, multiple single step traversals can be combined forming a complex traversal, analogous to how multiple basic graph patterns constitute a complex SPARQL query [83] .  ... 
arXiv:1910.03118v1 fatcat:wsww5vhlwjhqjlouibetb6mo3a

Querying Large-scale RDF Datasets Using the SANSA Framework

Claus Stadler, Gezim Sejdiu, Damian Graux, Jens Lehmann
2019 Zenodo  
In this paper we present Sparklify: a scalable software component for efficient evaluation of SPARQL queries over distributed RDF datasets.  ...  This work is motivated by the lack of Big Data SPARQL systems that are capable of exposing large-scale heterogeneous RDF datasets via a Web SPARQL endpoint.  ...  And, querying the data is essential to browse, search and explore the structured information. SPARQL, the RDF query language, is very expressive which allows extracting complex relationships.  ... 
doi:10.5281/zenodo.3567886 fatcat:qpmp6xk2gbb3tp5mtz35bhz4y4

Do We Need Specialized Graph Databases?

Anil Pacaci, Alice Zhou, Jimmy Lin, M. Tamer Özsu
2017 Proceedings of the Fifth International Workshop on Graph Data-management Experiences & Systems - GRADES'17  
Social networking applications pose new challenges to data management systems due to demand for real-time querying and manipulation of the graph structure.  ...  With the advent of online social networks, there is an increasing demand for storage and processing of graph-structured data.  ...  ACKNOWLEDGMENTS This research was supported by multiple Discovery Grants from the Natural Sciences and Engineering Research Council (NSERC) of Canada.  ... 
doi:10.1145/3078447.3078459 dblp:conf/grades/PacaciZLO17 fatcat:d3v735oe5rfwhlcg6jei4rq3ti

Knowledge-infused and consistent Complex Event Processing over real-time and persistent streams

Qunzhi Zhou, Yogesh Simmhan, Viktor Prasanna
2017 Future generations computer systems  
We validate our query model using domain-aware CEP queries from a real-world Smart Power Grid application, and experimentally analyze the benefits of our optimizations for executing these queries, using  ...  Emerging applications in Internet of Things (IoT) and Cyber-Physical Systems (CPS) present novel challenges to Big Data platforms for performing online analytics.  ...  The views and opinions of authors expressed herein do not necessarily state or reflect those of the US Government or any agency thereof.  ... 
doi:10.1016/j.future.2016.10.030 fatcat:gvqp34dfvbfwjbefip5cu35tsm

Efficient Distributed SPARQL Queries on Apache Spark

Saleh Albahli
2019 International Journal of Advanced Computer Science and Applications  
We further experimented with the performance of queries using distributed SPARQL query on Apache Spark GraphX and studied different stages involved in this pipeline.  ...  The execution of distributed SPARQL query on Apache Spark GraphX helped us study its performance and gave insights into which stages of the pipeline can be improved.  ...  Schätzle [9] aimed to optimize SPARQL queries in order to reduce their execution time.  ... 
doi:10.14569/ijacsa.2019.0100874 fatcat:lolh5mvrhrgttjdfm3uqbrqdam

One Size Does Not Fit All: Querying Web Polystores

Yasar Khan, Antoine Zimmermann, Alokkumar Jha, Vijay Gadepally, Mathieu D'Aquin, Ratnesh Sahay
2019 IEEE Access  
INDEX TERMS Databases, world wide web, query federation, query optimization, query planning, linked data, SPARQL, healthcare, and life sciences. 9598 2169-3536  ...  and 2) query optimization, join, and execution over different data models.  ...  Also, the unlimited use of optional parts in a SPARQL query could lead to high complexity [46] .  ... 
doi:10.1109/access.2018.2888601 fatcat:xpwuxf63dzg5lcnqn6mqwbtwou

An Analytical Study of Large SPARQL Query Logs [article]

Angela Bonifati, Wim Martens, Thomas Timm
2017 arXiv   pre-print
for SPARQL query evaluation, query optimization, tuning, and benchmarking.  ...  In this paper, we conduct an in-depth analytical study of the queries formulated by end-users and harvested from large and up-to-date query logs from a wide variety of RDF data sources.  ...  query logs analysed in this paper.  ... 
arXiv:1708.00363v1 fatcat:efphtmyxdnalvjryrmlebru5wq
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