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Keyword Search over Federated RDF Datasets

Yenier Izquierdo, Marco A. Casanova, Grettel García, Frederic Dartayre, Carlos Henrique Levy
2017 International Conference on Conceptual Modeling  
This paper describes an algorithm to perform keyword search over federated RDF datasets.  ...  The algorithm compiles keyword-based queries into federated SPARQL queries, without user intervention, under the assumption that the RDF datasets and the federation have a schema.  ...  The SPARQL Protocol and RDF Query Language (SPARQL) was officially introduced in 2008 to specify queries over RDF datasets.  ... 
dblp:conf/er/IzquierdoCGDL17 fatcat:6b6gwy2bubb4xaq5egvvcmvj2u

A Platform for Keyword Search and its Application for COVID-19 Pandemic Data

Yenier T. Izquierdo, Grettel M. Garcia, Melissa Lemos, Alexandre Novello, Bruno Novelli, Cleber Damasceno, Luiz André P. P. Leme, Marco A. Casanova
2021 Journal of Information and Data Management  
However, recently, keyword search has been expanded to relational databases and RDF datasets, as an attractive alternative to traditional database access.  ...  The paper ends with the description of an application, called CovidKeyS, which uses DANKE to implement keyword search over three COVID-19 data scenarios.  ...  Finally, an approach for keyword search for temporal RDF graphs that automatically compiles keyword queries into a set of candidate SPARQL queries was presented in [Gkirtzou et al. 2015 ].  ... 
doi:10.5753/jidm.2021.1904 fatcat:gnopcwab2jcbrfa65n6z4atu4q

Enabling Automatic Discovery and Querying of Web APIs at Web Scale using Linked Data Standards

Franck Michel, Catherine Faron-Zucker, Olivier Corby, Fabien Gandon
2019 Companion Proceedings of The 2019 World Wide Web Conference on - WWW '19  
We apply these principles to the concrete case of SPARQL micro-services that aim at querying Web APIs using SPARQL.  ...  We report on a prototype implementation that is available on-line for test purposes, and that can be effectively discovered using Google's Dataset Search engine.  ...  An application willing to carry out a certain task first queries search engines (step 2) for datasets matching certain keywords.  ... 
doi:10.1145/3308560.3317073 dblp:conf/www/MichelFCG19 fatcat:efmlsfnh5jcjncsdg3mx4p2zx4

Bio-SODA: Enabling Natural Language Question Answering over Knowledge Graphs without Training Data [article]

Ana Claudia Sima, Tarcisio Mendes de Farias, Maria Anisimova, Christophe Dessimoz, Marc Robinson-Rechavi, Erich Zbinden, Kurt Stockinger
2021 arXiv   pre-print
available KGQA systems by an F1-score of least 20% and by an even higher factor on more complex bioinformatics datasets.  ...  Bio-SODA uses a generic graph-based approach for translating user questions to a ranked list of SPARQL candidate queries.  ...  ACKNOWLEDGMENTS We thank the Swiss National Science Foundation for funding (NRP 75, grant 407540_167149), Lukas Blunschi for the implementation of the SODA system for keyword search system over relational  ... 
arXiv:2104.13744v4 fatcat:swbggfd34ng7fgh7qaiqokvxa4

Querying Heterogeneous Datasets on the Linked Data Web: Challenges, Approaches, and Trends

Andre Freitas, Edward Curry, Joao Gabriel Oliveira, Sean O'Riain
2012 IEEE Internet Computing  
Acknowledgments This work has been funded by Science Foundation Ireland under grant number SFI/08/CE/I1380 (Lion-2). We thank the reviewers and editors for their careful and valuable feedback.  ...  Existing approaches range from less expressive queries, based on keyword search over textual information associated with the dataset entities, to star-shaped queries and hybrid queries (that is, queries  ...  interface Indexer Dataset Dataset Index Updater Crawler Reasoner Dataset updater (b) (c) (d) Keyword index Datasets Datasets SPARQL query engine SPARQL query Concept  ... 
doi:10.1109/mic.2011.141 fatcat:kovzfmfjvfhpdeavhxcb3pueba

Querying and Searching Heterogeneous Knowledge Graphs in Real-time Linked Dataspaces [chapter]

André Freitas, Seán O'Riáin, Edward Curry
2019 Real-time Linked Dataspaces  
by the search and query service.  ...  Section 7.3 introduces search and query over dataspaces, discusses the challenges with data heterogeneity in a dataspace, and identifies the core requirement for the search and query service.  ...  Existing approaches range from less expressive queries, based on keyword search over textual information associated with the dataset entities, to star-shaped queries and hybrid queries (i.e. queries mixing  ... 
doi:10.1007/978-3-030-29665-0_7 fatcat:7qb2boh7njgvjiknknaaig5cou

Distributed SPARQL over Big RDF Data: A Comparative Analysis Using Presto and MapReduce

Mulugeta Mammo, Srividya K. Bansal
2015 2015 IEEE International Congress on Big Data  
The map-reduce program loads RDF data into HDFS while the compiler translates SPARQL queries into a subset of SQL that Presto (and Hive) can understand.  ...  The evaluation was done on four and eight node Linux clusters installed on Microsoft Windows Azure platform with RDF datasets of size 10, 20, and 30 million triples.  ...  A query language standard, SPARQL, has also been developed to query RDF datasets.  ... 
doi:10.1109/bigdatacongress.2015.15 dblp:conf/bigdata/MammoB15 fatcat:reiximps5ragvnqnynsm735m7a

A Framework for Exploration and Visualization of SPARQL Endpoint Information

Maria Krommyda
2020 International Journal of Graph Computing  
The SPARQL query language alleviates this barrier by facilitating the exploration of this information and many data providers have created dedicated SPARQL endpoints for their data.  ...  The platform handles each query result independently based only on its characteristics, offering an endpoint and data schema agnostic solution.  ...  Acknowledgment The experimental analysis presented in Section 6 was supported by Mr. Tara Venkata Sai Rahul Muktineni as part of his Master Project for the University of Ottawa.  ... 
doi:10.35708/gc1868-126723 fatcat:nc5n6fwkjne2rofkajcpz4oczu

Gravsearch: Transforming SPARQL to query humanities data

Tobias Schweizer, Benjamin Geer, Antonis Bikakis, Beatrice Markhoff, Alessandro Mosca, Stephane Jean, Eero Hyvönen
2020 Semantic Web Journal  
It does this by introducing server software that mediates between the client and the triplestore, transforming an input SPARQL query into one or more queries executed by the triplestore.  ...  Gravsearch (Virtual Graph Search), a SPARQL transformer developed as part of a web-based API, is designed to support complex searches that are desirable in humanities research, while avoiding these disadvantages  ...  Acknowledgements This work was supported by the Swiss National Science Foundation (166072) and the Swiss Data and Service Center for the Humanities.  ... 
doi:10.3233/sw-200386 fatcat:hooqro2axfdgnmwx7u2va7r5pi

Scalable Keyword Search on Large RDF Data

Wangchao Le, Feifei Li, Anastasios Kementsietsidis, Songyun Duan
2014 IEEE Transactions on Knowledge and Data Engineering  
Keyword search is a useful tool for exploring large RDF datasets.  ...  Given a keyword query, the summaries lend significant pruning powers to exploratory keyword search and result in much better efficiency compared to previous works.  ...  SCHEMA generates a set of k SPARQL queries for each keyword query. Evaluating these queries are supposed to return k answer roots ranked by the scores.  ... 
doi:10.1109/tkde.2014.2302294 fatcat:dqaonuvykrf2hf3dtbyjptnnue

G-SPARQL

Sherif Sakr, Sameh Elnikety, Yuxiong He
2012 Proceedings of the 21st ACM international conference on Information and knowledge management - CIKM '12  
We describe an algebraic compilation mechanism for our proposed query language which is extended from the relational algebra and based on the basic construct of building SPARQL queries, the Triple Pattern  ...  We propose a SPARQL-like language, G-SPARQL, for querying attributed graphs.  ...  in the RDF dataset.  ... 
doi:10.1145/2396761.2396806 dblp:conf/cikm/SakrEH12 fatcat:aeagal3dmzcu5meclzblkrlv3u

Local Type Checking for Linked Data Consumers

Gabriel Ciobanu, Ross Horne, Vladimiro Sassone
2013 Electronic Proceedings in Theoretical Computer Science  
The Web of Linked Data is the cumulation of over a decade of work by the Web standards community in their effort to make data more Web-like.  ...  The type system is based on the fragment of the SPARQL, RDF Schema and OWL recommendations that deals with simple data types.  ...  Most datasets, including data from DBpedia, conform to this typing pattern. Further weight is added by the Facebook Open Graph protocol which demands typing at exactly the level we deliver.  ... 
doi:10.4204/eptcs.123.4 fatcat:n7eurqyok5hclaqwpnzljayove

A survey of RDF storage approaches

David C. Faye, Olivier Curé, Guillaume Blin
2012 ARIMA  
Efficient data storage and query processing that can scale to large amounts of possibly schema-less data has become an important research topic.  ...  As datasets grow larger and more datasets are linked together, scalability becomes more important.  ...  The proposal is based on a set of semantic query rewriting rules to improve query performance by reasoning over the ontology schema of the RDF triples.  ... 
doi:10.46298/arima.1956 fatcat:j2zjgg4dvzhmjm7qoimwzknjc4

A Stitch in Time Saves Nine -- SPARQL querying of Property Graphs using Gremlin Traversals [article]

Harsh Thakkar and Dharmen Punjani and Yashwant Keswani and Jens Lehmann and Sören Auer
2018 arXiv   pre-print
We present Gremlinator, a novel SPARQL to Gremlin translator. Gremlinator translates SPARQL queries to Gremlin traversals for executing graph pattern matching queries over graph databases.  ...  Our evaluation demonstrates the substantial performance gain obtained by the Gremlin counterparts of the SPARQL queries, especially for star-shaped and complex queries.  ...  Acknowledgements This work is supported by the funding received from EU-H2020 WDAqua ITN (GA. 642795). We would like to thank Dr. Marko Rodriguez, Mr. Stephen Mallette, and Mr.  ... 
arXiv:1801.02911v2 fatcat:nz2kgbff7zfkbhocnrhelo5bfu

Expressive and Scalable Query-Based Faceted Search over SPARQL Endpoints [chapter]

Sébastien Ferré
2014 Lecture Notes in Computer Science  
In this paper, we further reconcile QFS with scalability and portability by building QFS over SPARQL endpoints. We also improve expressivity and readability.  ...  In a previous work, we have proposed Query-based Faceted Search (QFS) as a way to reconcile the expressivity of formal languages and the usability of faceted search.  ...  designing, implementing, and experimenting a first version of QFS over SPARQL endpoints.  ... 
doi:10.1007/978-3-319-11915-1_28 fatcat:kxbbe7j5pzbxleolyo3fjavsui
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