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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 strategy introduces rearrangement of order of triple pattern using Differential Evolution(DE). The experimental study focus on main-memory model of RDF data and ARQ query engine of Jena.  ...  [26] presented a technique for the static query optimization for reordering of triple pattern of BGP.  ... 
doi:10.5815/ijcnis.2018.03.06 fatcat:h4jizd5uxza6tfn7d7aikw3xju

A Survey of RDF Stores SPARQL Engines for Querying Knowledge Graphs [article]

Waqas Ali, Muhammad Saleem, Bin Yao, Aidan Hogan, Axel-Cyrille Ngonga Ngomo
2021 arXiv   pre-print
RDF has seen increased adoption in recent years, prompting the standardization of the SPARQL query language for RDF, and the development of local and distributed engines for processing SPARQL queries.  ...  techniques for efficiently evaluating SPARQL queries in a local setting (on one machine).  ...  The Jena ARQ library is used to parse SPARQL queries into an algebra tree, where optimizations for filters and selectivity-based join reordering are applied.  ... 
arXiv:2102.13027v4 fatcat:phontczhbfcvdjt5y75n3hfcge

Teaching Learning Based Optimization in Semantic Web of Distributed RDF

2019 International journal of recent technology and engineering  
In this research, the Teacher Learning based Optimization (TLBO) algorithm is proposed for the query optimization to reduce query cost, and optimize the computation time of the query.  ...  The TLBO technique select the suitable location and size of the population based on the data that effectively provide the solution for the distributed data i.e.., triple pattern of semantic web.  ...  Birant [13] implemented a method for SPARQL queries optimization with different shapes of graphs. This technique reordered the triple based on Ant Colony Optimization (ACO) technique.  ... 
doi:10.35940/ijrte.b3191.078219 fatcat:fjikl576r5foxmwwtckm6fpzd4

A Machine Learning Approach to SPARQL Query Performance Prediction

Rakebul Hasan, Fabien Gandon
2014 2014 IEEE/WIC/ACM International Joint Conferences on Web Intelligence (WI) and Intelligent Agent Technologies (IAT)  
Traditional approaches for estimating SPARQL query cost are based on statistics about the underlying data.  ...  In this paper we address the problem of predicting SPARQL query performance. We use machine learning techniques to learn SPARQL query performance from previously executed queries.  ...  [23] present optimization techniques with pre-computed statistics for reordering triple patters in a SPARQL query for efficient query processing.  ... 
doi:10.1109/wi-iat.2014.43 dblp:conf/webi/HasanG14 fatcat:ra4xpxe4yba5fe3cr2cd3fmi64

Highly Parallel SPARQL Engine for RDF [chapter]

Fan Feng, Weikang Zhou, Ding Zhang, Jinhui Pang
2020 Communications in Computer and Information Science  
In this paper, a highly parallel batch processing engine is designed for SPARQL queries.  ...  Experiments show that the engine can optimize time and maximize the use of memory when processing batch SPARQL queries.  ...  The existing multi-query optimizations [MQO] [12] are based on finding common parts of batch queries and processing them to get answers.  ... 
doi:10.1007/978-981-15-7981-3_5 fatcat:axncaghjxncmpcss4gvkzksfgu

Predicting SPARQL Query Performance and Explaining Linked Data [chapter]

Rakebul Hasan
2014 Lecture Notes in Computer Science  
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.  ...  Moreover, consumers of the Semantic Web data may need explanations for debugging or understanding the reasoning behind producing the data.  ...  [27] present optimization techniques with pre-computed statistics for reordering triple patterns in a SPARQL query for efficient query processing.  ... 
doi:10.1007/978-3-319-07443-6_53 fatcat:h7xxf6wr4bfcjmysyiruee22im

Learning-based SPARQL query performance modeling and prediction

Wei Emma Zhang, Quan Z. Sheng, Yongrui Qin, Kerry Taylor, Lina Yao
2017 World wide web (Bussum)  
Performance characteristics, such as the execution time and memory usage, can help data consumers identify unexpected long-running queries before they start and estimate the system workload for query scheduling  ...  Extensive works address such issues in traditional SQL queries but they are not directly applicable when dealing with SPARQL queries.  ...  SPARQL query optimization RDBMS-based triple stores rely on the query optimization techniques of the relational database systems to evaluate SPARQL queries.  ... 
doi:10.1007/s11280-017-0498-1 fatcat:2mmbwvizwrgctcsg723pf5feeq

Using Triple Pattern Fragments to Enable Streaming of Top-k Shortest Paths via the Web [chapter]

Laurens De Vocht, Ruben Verborgh, Erik Mannens
2016 Communications in Computer and Information Science  
To address this, we propose an approach to top-k shortest pathfinding, which optimally translates a pathfinding query into sequences of triple pattern fragment requests.  ...  We explain how this approach behaves using a training dataset, a subset of DBpedia with 10 million triples, and show the trade-offs to a SPARQL approach where all the data is gathered in a single triple  ...  , the Institute for the Promotion of Innovation by Science and Technology in Flanders (IWT), the Fund for Scientific Research-Flanders (FWO-Flanders), and the European Union.  ... 
doi:10.1007/978-3-319-46565-4_18 fatcat:hwtibfn56fdrxetmm2qpfoxtfy

Rewriting queries on SPARQL views

Wangchao Le, Songyun Duan, Anastasios Kementsietsidis, Feifei Li, Min Wang
2011 Proceedings of the 20th international conference on World wide web - WWW '11  
In this paper, we present the first native query rewriting algorithm for SPARQL.  ...  For an input SPARQL query over a set of virtual SPARQL views, the rewritten query resembles a union of conjunctive queries and can be of exponential size.  ...  as the base data, over which views are defined using SPARQL queries.  ... 
doi:10.1145/1963405.1963497 dblp:conf/www/LeDKLW11 fatcat:2n2hzhilqrc3hmtq33lar6xnrm

Bridging the Semantic Web and NoSQL Worlds: Generic SPARQL Query Translation and Application to MongoDB [chapter]

Franck Michel, Catherine Faron-Zucker, Johan Montagnat
2019 Lecture Notes in Computer Science  
Its JSON-based data model and its query language differ greatly from SQL-based systems for which many rewriting works have been proposed.  ...  Chebotko's algorithm [10] focused on RDB-based triple stores. Priyatna et al.  ... 
doi:10.1007/978-3-662-58664-8_5 fatcat:ixku3mam5zdclftctvv4jmkx7m

SPARQL basic graph pattern optimization using selectivity estimation

Markus Stocker, Andy Seaborne, Abraham Bernstein, Christoph Kiefer, Dave Reynolds
2008 Proceeding of the 17th international conference on World Wide Web - WWW '08  
We define and analyze the characteristics of heuristics for selectivity-based static BGP optimization.  ...  In this paper, we formalize the problem of Basic Graph Pattern (BGP) optimization for SPARQL queries and main memory graph implementations of RDF data.  ...  INTRODUCTION In this paper, we focus on selectivity-based static Basic Graph Pattern (BGP) optimization for SPARQL queries [14] and main memory graph implementations of RDF [9] data.  ... 
doi:10.1145/1367497.1367578 dblp:conf/www/StockerSBKR08 fatcat:53o7miyozve4fdjruk5l3i62qe

SOWL QL: Querying Spatio-Temporal Ontologies in OWL

Konstantinos Stravoskoufos, Euripides G. M. Petrakis, Nikolaos Mainas, Sotirios Batsakis, Vasilis Samoladas
2016 Journal on Data Semantics  
We introduce SOWL QL, a query language for spatio-temporal information in ontologies.  ...  Query translation in SOWL QL yields SPARQL queries implying that, querying spatio-temporal ontologies using SPARQL is still feasible but suffers from several drawbacks the most important of them being  ...  Query optimization is an important direction for future work: optimizing SOWL QL might require that Jena ARQ is extended (or replaced by a new query mechanism possibly skipping translation to SPARQL) for  ... 
doi:10.1007/s13740-016-0064-5 fatcat:i5ybyrwvt5c37coelih72lv3cm

Efficient Query Processing in RDF Databases [chapter]

Andrey Gubichev, Thomas Neumann
2014 Emerging Directions in Database Systems and Applications  
Since the high-performance RDF systems are often implemented as triple stores (i.e., they represent RDF data as a single table with three attributes, at least conceptually), the query optimization strategies  ...  In this paper we show that the techniques borrowed from traditional SQL query optimization (such as Dynamic Programming algorithm or greedy heuristics) are not immediately capable of handling large SPARQL  ...  Sec. 2 introduces the concepts of cost-based SPARQL query optimization. Sec. 3 demonstrates the unique query optimization challenges caused by the nature of RDF data.  ... 
doi:10.1201/b16859-8 fatcat:xu6mdl3uvnhmzcvzdbap2i2eiq


Wouter Beek, Javier D. Fernández, Ruben Verborgh
2017 Proceedings of the 13th International Conference on Semantic Systems - Semantics2017  
LOD-a-lot is a dataset that integrates a large portion (over 28 billion triples) of the LOD Cloud into a single ready-to-consume le that can be easily downloaded, shared and queried with a small memory  ...  Many data scientists make use of Linked Open Data (LOD) as a huge interconnected knowledge base represented in RDF.  ...  On-demand metrics of estimated result set size (Section 2.3) can be used in query rewriting. Speci cally, SPARQL Basic Graph Pa ern evaluation can be optimized by reordering based on result set size.  ... 
doi:10.1145/3132218.3132241 dblp:conf/i-semantics/BeekFV17 fatcat:3vl3smlzsrfzpaihuyomvhpmvi

Cluster-Based Join for Geographically Distributed Big RDF Data

Fan Yang, Adina Crainiceanu, Zhiyuan Chen, Don Needham
2019 2019 IEEE International Congress on Big Data (BigDataCongress)  
This paper introduces CBTP, a novel join algorithm that takes advantage of network topology to decrease the cost of processing SPARQL queries in a geographically distributed environment.  ...  The performance of these systems can be poor for large and geographically distributed RDF data where network transfer costs are high.  ...  Because statistics-based query optimization was not enabled in the underlying system, for each query tested, we manually reordered the triple patterns such that the most selective triple pattern was evaluated  ... 
doi:10.1109/bigdatacongress.2019.00037 dblp:conf/bigdata/YangCCN19 fatcat:lgvvzxoekbhwlixw2y4al4scsa
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