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On the Formulation of Performant SPARQL Queries

Antonis Loizou, Renzo Angles, Paul Thomas Groth
2015 Social Science Research Network  
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  ...  The combination of the flexibility of RDF and the expressiveness of SPARQL provides a powerful mechanism to model, integrate and query data.  ...  Acknowledgements The research leading to these results has received support from the Innovative Medicines Initiative Joint Undertaking under grant agreement number 115191, resources of which are composed  ... 
doi:10.2139/ssrn.3199178 fatcat:22upsfwqufabrevgcwn3azbtr4

On the formulation of performant SPARQL queries

Antonis Loizou, Renzo Angles, Paul Groth
2015 Journal of Web Semantics  
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  ...  The combination of the flexibility of RDF and the expressiveness of SPARQL provides a powerful mechanism to model, integrate and query data.  ...  Acknowledgements The research leading to these results has received support from the Innovative Medicines Initiative Joint Undertaking under grant agreement number 115191, resources of which are composed  ... 
doi:10.1016/j.websem.2014.11.003 fatcat:lb55lstdbjfmvcrf2bqb4lcr5q

Federated Query Formulation and Processing through BioFed

Ali Hasnain, Syeda Sana e Zainab, Durre Zehra, Qaiser Mehmood, Muhammad Saleem, Dietrich Rebholz-Schuhmann
2017 Extended Semantic Web Conference  
The data in the LS requires integration and current integrative solutions increasingly rely on the federation of queries for distributed resources.  ...  BioFed enables user to formulate as well as execute both federated and non-federated SPARQL queries over more than 130 public LS SPARQL endpoints.  ...  Acknowledgements The work presented in this paper has been partly funded by EU FP7 GRANA-TUM project (project number 270139) and Science Foundation Ireland under Grant No. SFI/12/RC/2289.  ... 
dblp:conf/esws/HasnainZZM0R17 fatcat:xy5gqunsgzferl4ussvzsbeytm

ASQFor: Automatic SPARQL query formulation for the non-expert

Muhammad Rizwan Saeed, Charalampos Chelmis, Viktor K. Prasanna, Carlos Linares López
2018 AI Communications  
We demonstrate via extensive experimentation that ASQFor significantly speeds up the construction of query formulation while at the same time matching the precision and recall of hand-crafted optimized  ...  Specifically, we propose Automatic SPARQL Query Formulation (ASQFor), a systematic framework to issue semantic queries over RDF repository using simple concept-based search primitives.  ...  Effect of Automation on Query Formulation Time To evaluate the performance of ASQFor in formulating queries, we measured the time required to generate the representative queries shown in Table 1 .  ... 
doi:10.3233/aic-170746 fatcat:imtwyphztnh4td7u7il7huoqge

Investigating Learnability, User Performance, and Preferences of the Path Query Language SemwidgQL Compared to SPARQL [chapter]

Timo Stegemann, Jürgen Ziegler
2017 Lecture Notes in Computer Science  
To assess the applicability of SemwidgQL in real applications, we analyzed its expressiveness based on a large corpus of observed Sparql queries, showing that the language covers more than 90% of the typical  ...  queries performed on Linked Data.  ...  Efficiency was measured by the participants' performance measures for the query formulation tasks.  ... 
doi:10.1007/978-3-319-68288-4_36 fatcat:upispofegvhgdkkfo6of7ztgem

MashQL

Mustafa Jarrar, Marios D. Dikaiakos
2008 Proceeding of the 2nd international workshop on Ontologies and nformation systems for the semantic web - ONISW '08  
Each internet data source is seen as a table, and a mashup is seen as a query on these tables. We assume that web data sources are represented in RDF, and SPARQL is the query language.  ...  In the background, MashQL queries are translated into and executed as SPARQL queries.  ...  Acknowledgement We are indebted to George Pallis for his valuable comments and feedback on the early drafts of this paper.  ... 
doi:10.1145/1458484.1458499 dblp:conf/cikm/JarrarD08 fatcat:kpbkdabtwbepdcma43defa5j3e

A distributed query execution engine of big attributed graphs

Omar Batarfi, Radwa Elshawi, Ayman Fayoumi, Ahmed Barnawi, Sherif Sakr
2016 SpringerPlus  
Our experimental evaluation shows the efficiency and the scalability of DG-SPARQL on querying massive attributed graph datasets in addition to its ability to outperform the performance of Apache Giraph  ...  This article describes the design, implementation in addition to the performance evaluation of DG-SPARQL, a distributed, hybrid and adaptive parallel execution engine of G-SPARQL queries.  ...  Competing interests The authors declare that they have no competing interests. Received: 15 January 2016 Accepted: 27 April 2016  ... 
doi:10.1186/s40064-016-2251-0 pmid:27350905 pmcid:PMC4899405 fatcat:midt5lr2djg2jogjvpbmv4njly

Towards a Top-K SPARQL Query Benchmark

Shima Zahmatkesh, Emanuele Della Valle, Daniele Dell'Aglio, Alessandro Bozzon
2014 International Semantic Web Conference  
The research on optimization of top-k SPARQL query would largely benefit from the establishment of a benchmark that allows comparing different approaches.  ...  In this paper we propose Top-k DBPSB: an extension of the DBpedia SPARQL benchmark (DBPSB), a benchmark known to resemble reality, with the capabilities required to compare SPARQL engines on top-k queries  ...  In order to evaluate the performance of SPARQL engines, we use the DBpedia SPARQL Benchmark test driver and modify it for Top-k queries.  ... 
dblp:conf/semweb/ZahmatkeshVDB14 fatcat:xr64jd25dbc7xbaaw24hyaspyy

QueDI: From Knowledge Graph Querying to Data Visualization [chapter]

Renato De Donato, Martina Garofalo, Delfina Malandrino, Maria Angela Pellegrino, Andrea Petta, Vittorio Scarano
2020 Lecture Notes in Computer Science  
The main novelty of our approach is the split of the querying phase in SPARQL query building and data table manipulation.  ...  While Open Data (OD) publishers are spur in providing data as Linked Open Data (LOD) to boost innovation and knowledge creation, the complexity of RDF querying languages, such as SPARQL, threatens their  ...  Thus, we both consider the English NL formulation of the query and the related SPARQL query while performing them on QueDI.  ... 
doi:10.1007/978-3-030-59833-4_5 fatcat:qrf3dopt55exbglp2fpyt6oqbe

Multilingual Natural Language Interaction with Semantic Web Knowledge Bases and Linked Open Data [chapter]

Mariana Damova, Dana Dannélls, Ramona Enache, Maria Mateva, Aarne Ranta
2014 Towards the Multilingual Semantic Web  
This unique solution includes several steps of transition from natural language to SPARQL and from RDF to coherent multilingual descriptions, using the Grammatical Framework, GF.  ...  The approach builds on a semantic knowledge infrastructure in RDF, it is based on OWLIM-SE and the data integration method Reason-able View supplied with an ontological reference layer.  ...  One of the bottlenecks of SPARQL is that formulating a query requires knowledge of the query language and of the schemata underlying the datasets in the knowledge representation infrastructure.  ... 
doi:10.1007/978-3-662-43585-4_13 fatcat:shdo2klmpjaubhotjx65f5eat4

Towards a Top-K SPARQL Query Benchmark Generator

Shima Zahmatkesh
2014 International Semantic Web Conference  
The research on optimization of top-k SPARQL query would largely benefit from the establishment of a benchmark that allows comparing different approaches.  ...  In this paper we propose Top-k DBPSB: an extension of the DBpedia SPARQL benchmark (DBPSB), a benchmark known to resemble reality, with the capabilities required to compare SPARQL engines on top-k queries  ...  The Berlin SPARQL Benchmark (BSBM) [1] is one of the earliest benchmarks for SPARQL engines. It is based on an e-commerce use case. The queries contain various SPARQL features.  ... 
dblp:conf/semweb/Zahmatkesh14 fatcat:fu3hyeytlbg3hn2ofnwl7xrshu

R2D2: A Dbpedia Chatbot Using Triple-Pattern Like Queries

Haridimos Kondylakis, Dimitrios Tsirigotakis, Giorgos Fragkiadakis, Emmanouela Panteri, Alexandros Papadakis, Alexandros Fragkakis, Eleytherios Tzagkarakis, Ioannis Rallis, Zacharias Saridakis, Apostolos Trampas, Giorgos Pirounakis, Nikolaos Papadakis
2020 Algorithms  
Based on user input (in the form of triple-pattern like queries), the corresponding SPARQL queries are automatically formulated.  ...  The usability evaluation performed shows the advantages of our solution and its usefulness.  ...  We instructed them to perform at will at least 3 queries with at least one of them including more than one triple pattern.  ... 
doi:10.3390/a13090217 fatcat:tvllkaq74fdltjazt3vmgxi6py

Semantic Search based on Ontology Alignment for Information Retrieval

Manju Mony, Jyothi M. Rao, Manish M. Potey
2014 International Journal of Computer Applications  
Traditional search is keyword based search and does not focus on relationship between the words. In semantic search, the search is performed on basis of the meaning of the terms and concepts.  ...  Resource Description Framework (RDF) is used as the data model and SPARQL query language is used to query the RDF data. Currently, there is lot of RDF based data set, e.g.  ...  ACKNOWLEDGEMENTS We wish to thank Insurance Information Bureau of India (IIB), for allowing us to use the health insurance statistics data at https://iib.gov.in/IRDA/homePageAction.do?  ... 
doi:10.5120/18789-0125 fatcat:bpf4whldmrdrvptwoej5a6kve4

Introducing RDF Graph Summary with Application to Assisted SPARQL Formulation

Stephane Campinas, Thomas E. Perry, Diego Ceccarelli, Renaud Delbru, Giovanni Tummarello
2012 2012 23rd International Workshop on Database and Expert Systems Applications  
One of the reasons for the slow adoption of SPARQL is the complexity in query formulation due to data diversity.  ...  Our method is based on a summary of the data graph and assists the user during an interactive query formulation by recommending possible structural query elements.  ...  ACKNOWLEDGEMENTS This material is based upon works supported by the European FP7 projects LOD2 (257943) and SEMLIB (FP7-SME-2010-1-SEMLIB 262301) and by Science Foundation Ireland under Grant No.  ... 
doi:10.1109/dexa.2012.38 dblp:conf/dexaw/CampinasPCDT12 fatcat:wlskqy5sp5hqbcwqthd5svxb4e

BioFed: federated query processing over life sciences linked open data

Ali Hasnain, Qaiser Mehmood, Syeda Sana e Zainab, Muhammad Saleem, Claude Warren, Durre Zehra, Stefan Decker, Dietrich Rebholz-Schuhmann
2017 Journal of Biomedical Semantics  
Our evaluation of BioFed against FedX is based on 20 heterogeneous federated SPARQL queries and shows competitive execution performance in comparison to FedX, which can be attributed to the provision of  ...  Suggested solutions are based on query federation approaches, which require the submission of SPARQL queries to endpoints.  ...  We also acknowledge Helena F Deus who contributed in the conceptualisation of initial versions of ARDI and QE.  ... 
doi:10.1186/s13326-017-0118-0 pmid:28298238 pmcid:PMC5353896 fatcat:ie4bsrw7dnh6hpxh7vy6672uha
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