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The Ontop Framework for Ontology Based Data Access [chapter]

Timea Bagosi, Diego Calvanese, Josef Hardi, Sarah Komla-Ebri, Davide Lanti, Martin Rezk, Mariano Rodríguez-Muro, Mindaugas Slusnys, Guohui Xiao
2014 Communications in Computer and Information Science  
The Ontop Framework Ontop is an open-source OBDA framework released under the Apache license, developed at the Free University of Bozen-Bolzano 1 and currently acts as the query transformation module of  ...  The main functionality of OBDA systems is query answering.  ...  This paper is supported by the EU under the large-scale integrating project (IP) Optique (Scalable End-user Access to Big Data), grant agreement n. FP7-318338.  ... 
doi:10.1007/978-3-662-45495-4_6 fatcat:77pqwm6dznf5nexppacg2oxfxa

How to Stay Ontop of Your Data: Databases, Ontologies and More [chapter]

Diego Calvanese, Benjamin Cogrel, Sarah Komla-Ebri, Davide Lanti, Martin Rezk, Guohui Xiao
2015 Lecture Notes in Computer Science  
In this demo, we use the recently developed NPD benchmark (+4 billion triples) to demonstrate the features of Ontop.  ...  First we use Ontop as a SPARQL end-point to load the ontology and mappings, and answer SPARQL queries. Then, we will show how to use Ontop to check inconsistencies and exploit SWRL ontologies.  ...  This paper is supported by the EU under the large-scale integrating project (IP) Optique (Scalable End-user Access to Big Data), grant agreement n. FP7-318338.  ... 
doi:10.1007/978-3-319-25639-9_4 fatcat:luiuwu6la5gubnkbwsw2xtferq

Ontology-based data access – Beyond relational sources

Elena Botoeva, Diego Calvanese, Benjamin Cogrel, Julien Corman, Guohui Xiao, Chiara Ghidini, Bernardo Magnini, Andrea Passerini
2019 Intelligenza Artificiale  
To enable access to such data, we generalize the well-known ontology-based data access (OBDA) framework so as to allow for querying arbitrary data sources using sparql.  ...  Then, to investigate feasibility of OBDA over non-relational DBs, we compare an implementation of an OBDA system over MongoDB, a popular json-document DB, with a triple store.  ...  We do so by instantiating the generalized OBDA framework over MongoDB as an extension of the OBDA system Ontop [6] , and comparing its performance with a triple store, which does not benefit from such  ... 
doi:10.3233/ia-190023 fatcat:yvfgbymmtjgsdo7pty22pkumx4

Ontology–based access to temporal data with Ontop: A framework proposal

Elem Güzel Kalayci, Sebastian Brandt, Diego Calvanese, Vladislav Ryzhikov, Guohui Xiao, Michael Zakharyaschev
2019 International Journal of Applied Mathematics and Computer Science  
We also propose a SPARQL-based query language for retrieving temporal information and, finally, an architecture of system implementation extending the state-of-the-art OBDA platform Ontop.  ...  However, classical OBDA systems do not support access to temporal data and reasoning over it. To address this issue, we propose a framework for temporal OBDA.  ...  This article is an extended and revised version of a paper that was published in the proceedings of the Workshop on Novel Techniques for Integrating Big Data (BigNovelTI 2017), co-located with the 21st  ... 
doi:10.2478/amcs-2019-0002 fatcat:oirwc33cnrcf3f3ba4fqzyiqki

Towards All-In-One OBDA Systems

Germán Alejandro Braun, Laura Andrea Cecchi, Pablo R. Fillottrani
2019 Joint Ontology Workshops  
The result is an extensible all-in-one framework with well-defined interfaces aimed at experimenting with different combination of tools.  ...  In this work we introduce the notion of configuration of an OBDA system, departing from a set of off-the-shelf tools that interoperate between each other in order to facilitate to users the access to data  ...  Thus, we outline on the inputs and outputs that diverse tools require and present the notion of configuration of an OBDA system departing from an all-in-one framework aiming at experimenting with diverse  ... 
dblp:conf/jowo/BraunCF19a fatcat:dk36jiefgfeorogk4fkba6xtwa

ANSWERING GEOSPARQL QUERIES OVER RELATIONAL DATA

K. Bereta, G. Xiao, M. Koubarakis
2017 The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences  
In this paper we present the system Ontop-spatial that is able to answer GeoSPARQL queries on top of geospatial relational databases, performing on-the-fly GeoSPARQL-to-SQL translation using ontologies  ...  This approach is more suitable in the cases where original datasets are stored in large relational databases (or generally in files with relational structure) and/or get frequently updated.  ...  ACKNOWLEDGEMENTS This work has been partially funded by the EU FP7 project OP-TIQUE (318338), the EU project Copernicus App Lab (730124), and the UNIBZ RTD project OBDAM (IN2045).  ... 
doi:10.5194/isprs-archives-xlii-4-w2-43-2017 fatcat:lxszfoiz6vbzfi72xunfhsn5re

Enhancing Virtual Ontology Based Access over Tabular Data with Morph-CSV [article]

David Chaves-Fraga, Edna Ruckhaus, Freddy Priyatna, Maria-Esther Vidal, Oscar Corcho
2021 arXiv   pre-print
We propose Morph-CSV, a framework for querying tabular data that exploits information from typical OBDA inputs (e.g., mappings, queries) to enforce constraints that can be used together with any SPARQL-to-SQL  ...  We compare and report the performance of two SPARQL-to-SQL OBDA engines, without and with the incorporation of MorphCSV.  ...  the creation of (YARR)RML mappings.  ... 
arXiv:2001.09052v2 fatcat:wabtn4ammnefbggt6j2w4dtqta

SPARQLing-Up the Web on-the-fly using Ontologies and Mappings

Konstantina Bereta, George Papadakis, Manolis Koubarakis
2018 International Workshop on Description Logics  
Ontop4theWeb is based on the system Ontop 2 [1], a state-of-the-art, opensource OBDA system that supports both R2RML and the OBDA mapping language.  ...  In this work, we introduce a framework for extending existing OBDA techniques to support querying of data from different sources that are available on the Web, such as webtables and Rest APIs.  ... 
dblp:conf/dlog/Bereta0K18 fatcat:32yk7uj5wrdnriu3rr7emsq72q

Ontop: Answering SPARQL queries over relational databases

Diego Calvanese, Benjamin Cogrel, Sarah Komla-Ebri, Roman Kontchakov, Davide Lanti, Martin Rezk, Mariano Rodriguez-Muro, Guohui Xiao, Óscar Corcho
2016 Semantic Web Journal  
We present Ontop, an open-source Ontology-Based Data Access (OBDA) system that allows for querying relational data sources through a conceptual representation of the domain of interest, provided in terms  ...  Key features of Ontop are its solid theoretical foundations, a virtual approach to OBDA, which avoids materializing triples and is implemented through the query rewriting technique, extensive optimizations  ...  This article is supported by the EU under the large-scale integrating project (IP) Optique (Scalable End-user Access to Big Data), grant agreement n. FP7-318338.  ... 
doi:10.3233/sw-160217 fatcat:mjwgfop5tvfvpf3rr6flpfvmwq

Integração Semântica das Bases de Dados do Município de São Paulo: Um Estudo de Caso com Anomalias Congênitas(Semantic Integration of Health Databases in São Paulo: A Case Study with Congenital Anomalies)

Débora Lina N. Ciriaco Pereira, Renata Wassermann, Laís Salvador
2018 Joint Seminar on Ontology Research in Brazil / International Workshop on Metamodels, Ontologies and Semantic Technologies  
This case study will evaluate two ontology based data access frameworks (Linked Data Mashup and Ontop) regarding integration quality (precision, completeness, and processing time to answer competence questions  ...  Here semantic data integration is the solution to provide precise information and answers questions like: how many individuals diagnosed with a congenital anomaly live in the city of São Paulo?  ...  Assim, inicialmente haverá a comparac ¸ão de dois frameworks de OBDA: Ontop e Linked Data Mashup (LDM).  ... 
dblp:conf/ontobras/PereiraWS18 fatcat:5ab3jy3hfjf63eeg4ylr3terxa

OBDA Over Non-Relational Databases

Elena Botoeva, Diego Calvanese, Benjamin Cogrel, Martin Rezk, Guohui Xiao
2016 Alberto Mendelzon Workshop on Foundations of Data Management  
We instantiate this framework to MongoDB, a popular JSON-document database, and implement a prototype extension of the virtual OBDA system Ontop for answering SPARQL queries over MongoDB.  ...  To facilitate access to such databases and to enable data integration of non-relational data sources, we generalize the well-known ontologybased data access (OBDA) framework so as to allow for querying  ...  OBDA Framework over MongoDB In this section we instantiate the generalized OBDA framework to MongoDB, a popular DB that stores collections of semi-structured JSON-style documents.  ... 
dblp:conf/amw/BotoevaCCRX16 fatcat:sv5ud5yz2nfkjbt4ebyupjeiae

Special issue of the Journal of Web Semantics on ontology-based data access

Diego Calvanese, Manolis Koubarakis, David Toman
2015 Journal of Web Semantics  
with inconsistencies in OBDA.  ...  The ontology-based data access (OBDA) paradigm was formulated a few years ago to tackle the problem of data integration, and more generally that of accessing data sources with a complex structure.  ...  Finally, the paper ''Efficient SPARQL-to-SQL with R2RML mappings'' by Mariano Rodríguez-Muro and Martin Rezk presents the rewriting techniques utilized by the open source OBDA system -ontop-(http://ontop.inf.unibz.it  ... 
doi:10.1016/j.websem.2015.06.001 fatcat:uqfd6zdr7vayvei2ylpuy7lzhy

Comparing Query Answering in OBDA Tools over W3C-Compliant Specifications

Manuel Namici, Giuseppe De Giacomo
2018 International Workshop on Description Logics  
In this W3C-compliant setting, we compare query answering in the two main tools for OBDA, namely, Mastro and Ontop, by resorting to the NPD Benchmark, and the fullfledged OBDA application developed for  ...  The Ontology-Based Data Access (OBDA) paradigm aims at providing to the users a unified and shared conceptual view of the domain of interest (ontology), while still enabling the data to be stored in different  ...  Ontop is an open source OBDA framework, written in Java, developed at the Free University of Bolzen-Bolzano and released under the terms of the Apache version 2.0 license.  ... 
dblp:conf/dlog/NamiciG18 fatcat:gusuynhicvfftnjqmez2hrca7m

On Information Disclosure in Ontology-based Data Access (Extended Abstract)

Gianluca Cima, Domenico Lembo, Lorenzo Marconi, Riccardo Rosati, Domenico Fabio Savo
2021 International Workshop on Description Logics  
This work was partly supported by the ANR AI Chair INTENDED (ANR-19-CHIA-0014), by the EU within the H2020 Programme under the grant agreement 834228 (ERC Advanced Grant WhiteMec) and the grant agreement  ...  825333 (MOSAICrOWN), by Regione Lombardia within the Call Hub Ricerca e Innovazione under the grant agreement 1175328 (WATCHMAN), and by the Italian MUR (Ministero dell'Università e della Ricerca) through  ...  In our work, we consider the more general Ontology-based Data Access (OBDA) framework, where an ontology is coupled to external data sources via a declarative mapping [14, 15] , and extend OBDA with CQE  ... 
dblp:conf/dlog/CimaLMRS21 fatcat:mcstqudtqfd2xggge7cjol2fqe

OBDA Beyond Relational DBs: A Study for MongoDB

Elena Botoeva, Diego Calvanese, Benjamin Cogrel, Martin Rezk, Guohui Xiao
2016 International Workshop on Description Logics  
We instantiate this framework to MongoDB, a popular JSON-document database, and implement an prototype extension of the virtual OBDA system Ontop for answering SPARQL queries over MongoDB.  ...  To facilitate access to such databases and to enable data integration of non-relational data sources, we generalize the well-known ontologybased data access (OBDA) framework so as to allow for querying  ...  This work is partially supported by the EU under IP project Optique (Scalable End-user Access to Big Data), grant agreement n. FP7-318338.  ... 
dblp:conf/dlog/BotoevaCCRX16 fatcat:bxqg2pfe2japlmqbs3kaqpfzpa
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