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Ontology-Based Data Access: Ontop of Databases [chapter]

Mariano Rodríguez-Muro, Roman Kontchakov, Michael Zakharyaschev
2013 Lecture Notes in Computer Science  
We discuss the theoretical foundations of Ontop: the tree-witness query rewriting, T -mappings and optimisations based on database integrity constraints and SQL features.  ...  We analyse the performance of Ontop in a series of experiments and demonstrate that, for standard ontologies, queries and data stored in relational databases, Ontop is fast, efficient and produces SQL  ...  Introduction Ontology-based data access (OBDA) [6, 11, 22] is regarded as a key ingredient for the new generation of information systems, especially for Semantic Web applications that involve large amounts  ... 
doi:10.1007/978-3-642-41335-3_35 fatcat:2v63lldztfahlhryhysdcr32ui


Henrihs Gorskis, Ludmila Aleksejeva, Inese Polaka
2017 Environment Technology Resources Proceedings of the International Scientific and Practical Conference  
This paper discusses the development and implementation of the ontology-based data access system, the ontology describing the medical data and the data mapping system, linking data from the database to  ...  The developed ontology-based data access system, described in this paper, provides a tool to store, manage and use definitions of common terminology and their mappings to the database.  ...  By basing ontology development directly on a database, and for the task of ontologybased data access, the likelihood of the concepts being usable and used in the task is higher.  ... 
doi:10.17770/etr2017vol2.2572 fatcat:kqyv2rwyr5b63l7bfbgbsb5vva

Ontology-Based Data Access with Databases: A Short Course [chapter]

Roman Kontchakov, Mariano Rodríguez-Muro, Michael Zakharyaschev
2013 Lecture Notes in Computer Science  
Ontology-based data access (OBDA) is regarded as a key ingredient of the new generation of information systems.  ...  In this chapter, we mainly focus on OBDA with the ontology language OWL 2 QL, one of the three profiles of the W3C standard Web Ontology Language OWL 2, and relational databases, although other possible  ...  Then what you need is ontology-based data access (OBDA, for short).  ... 
doi:10.1007/978-3-642-39784-4_5 fatcat:kn5f4iuvtrepdmgvk5bp7psn2i

Ontology-Based Data Access and Integration [chapter]

Diego Calvanese, Giuseppe De Giacomo, Domenico Lembo, Maurizio Lenzerini, Riccardo Rosati
2017 Encyclopedia of Database Systems  
One of the most interesting usages of shared conceptualizations is ontology-based data access.  ...  Furthermore, we provide means to access databases that are independent from the ontology, by proposing a novel mapping language that solves the so-called "impedance mismatch" between values in the databases  ...  Then, we look at the problem of accessing databases that are independent from the ontology. Observe, however, that such databases, being relational, store only values, not objects.  ... 
doi:10.1007/978-1-4899-7993-3_80667-1 fatcat:cyfckesenngyxcibe6mykqzy2q

Ontology-Based Data Access

Meghyn Bienvenu, Balder Ten Cate, Carsten Lutz, Frank Wolter
2014 ACM Transactions on Database Systems  
Ontology-based data access is concerned with querying incomplete data sources in the presence of domainspecific knowledge provided by an ontology.  ...  A central notion in this setting is that of an ontology-mediated query, which is a database query coupled with an ontology.  ...  For more expressive Horn ontology languages, FO rewritings and datalog rewritings are studied, for example, in Gottlob and Schwentick [2012] , Eiter et al. [2012] , Bienvenu et al. [2013a] , and Bárány  ... 
doi:10.1145/2661643 fatcat:evnh6sn7yvgk3kjz23nv2arsf4

Ontobroker: Ontology Based Access to Distributed and Semi-Structured Information [chapter]

Stefan Decker, Michael Erdmann, Dieter Fensel, Rudi Studer
1999 Database Semantics  
Furthermore, the generation of RDF descriptions enables the exploitation of the ontological information in RDF-based applications.  ...  The World Wide Web (WWW) can be viewed as the largest multimedia database that has ever existed. However, its support for query answering and automated inference is very limited.  ...  Additionally the metadata we generate is also direct content-based, thus allowing semantic-based access to web information.  ... 
doi:10.1007/978-0-387-35561-0_20 fatcat:kfca4xja5rg2pcbix6gsuluuoq

On the Top-k Retrieval Problem for Ontology-Based Access to Databases [chapter]

Umberto Straccia
2013 Studies in Computational Intelligence  
The chapter is a succinct summary on the problem of evaluating ranked top-k queries in the context of ontology-based access over relational databases.  ...  An ontology layer is used to define the relevant abstract concepts and relations of the application domain, while facts with associated score are stored into a relational database.  ...  On the Top-k Retrieval Problem for Ontology-Based Access to Databases  ... 
doi:10.1007/978-3-319-00954-4_5 fatcat:wq725kq5svcedjietrtez3rsaq

An Ontology-Based Architecture for Natural Language Access to Relational Databases [chapter]

Lawrence Muchemi, Fred Popowich
2013 Lecture Notes in Computer Science  
We demonstrate that an ontology-based approach is technically feasible to handle some of the challenges facing NL query processing for database access.  ...  Natural language (NL) access to databases is a problem that has interested researchers for many years.  ...  The Ontology-based Database Access Approach Our approach, which we call Ontology Concept Mapping (OCM), is intuitively derived from the way human beings reason.  ... 
doi:10.1007/978-3-642-39188-0_53 fatcat:hc6xcwnvm5b3hhgix3exbqmlji

Ontology-based database access with DIG-Mastro and the OBDA Plugin for Protégé (Demo Description)

Antonella Poggi, Mariano Rodriguez, Marco Ruzzi
2008 W3C Web Ontology Language (OWL) Experiences and Directions Workshop (OWLED)  
In Ontology Based Data Access (OBDA), the aim is to use an ontology to mediate access to data.  ...  The second component is the OBDA Plugin for Protégé, that in conjunction with the ontology editing features of Protégé, functions as an OBDA system designer.  ...  Ontology Based Data Access (OBDA).  ... 
dblp:conf/owled/PoggiRR08 fatcat:4sq2pb5njzbv7mxshxsjntgwje

Optimizing query rewriting in ontology-based data access

Floriana Di Pinto, Domenico Lembo, Maurizio Lenzerini, Riccardo Mancini, Antonella Poggi, Riccardo Rosati, Marco Ruzzi, Domenico Fabio Savo
2013 Proceedings of the 16th International Conference on Extending Database Technology - EDBT '13  
In ontology-based data access (OBDA), an ontology is connected to autonomous, and generally pre-existing, data repositories through mappings, so as to provide a high-level, conceptual view over such data  ...  the query); (ii) the query thus obtained is then reformulated over the database schema using the mapping assertions (mapping rewriting of the query).  ...  This research has been partially supported by the EU under FP7 project Optique -Scalable End-user Access to Big Data (grant n. FP7-318338).  ... 
doi:10.1145/2452376.2452441 dblp:conf/edbt/PintoLLMPRRS13 fatcat:molmzmjjubb2llkebwqbtijvou

The Complexity of Ontology-Based Data Access with OWL 2 QL and Bounded Treewidth Queries

Meghyn Bienvenu, Stanislav Kikot, Roman Kontchakov, Vladimir V. Podolskii, Vladislav Ryzhikov, Michael Zakharyaschev
2017 Proceedings of the 36th ACM SIGMOD-SIGACT-SIGAI Symposium on Principles of Database Systems - PODS '17  
Our concern is the overhead of answering OWL 2 QL ontology-mediated queries (OMQs) in ontology-based data access compared to evaluating their underlying tree-shaped and bounded treewidth conjunctive queries  ...  For OMQs with arbitrary ontologies and bounded-leaf CQs, NDL-rewritings are constructed and evaluated in LOGCFL.  ...  Introduction The main aim of ontology-based data access (OBDA) [49, 42] is to facilitate access to complex data for non-expert end-users.  ... 
doi:10.1145/3034786.3034791 dblp:conf/pods/BienvenuKKPRZ17 fatcat:pq2pdscf5zbzzkzn3lzqif2dlu

Ontology-based federated data access to human studies information

Ida Sim, Simona Carini, Samson W Tu, Landon T Detwiler, James Brinkley, Shamim A Mollah, Karl Burke, Harold P Lehmann, Swati Chakraborty, Knut M Wittkowski, Brad H Pollock, Thomas M Johnson (+2 others)
2012 AMIA Annual Symposium Proceedings  
The Human Studies Database project has developed an informatics infrastructure for federated query of human studies databases, using a generalizable approach to ontology-based data access.  ...  First, the Ontology of Clinical Research (OCRe) provides the reference semantics.  ...  A recent development is ontology-based data access (OBDA), which refers to the mediation of access to data repositories through ontologies that provide a high-level conceptual view of the data.  ... 
pmid:23304360 pmcid:PMC3540523 fatcat:oahd77qjjbetjajfp3rowk6ndm

Bootstrapping ontology-based data access specifications from relational databases [article]

Philipp Martis, Universität Stuttgart, Universität Stuttgart
This allows to benefit from ontology-based data access concepts without having to forbear from the advantages regarding performance and data consistency which is offered by relational database systems.  ...  Ontology-based data access (OBDA) is a useful approach to gain access to existing structured data in an easy and intuitive manner, abstracting from the representation of the data and thus releasing from  ...  source of structured information (see Section 2.1.2 -Ontology-based data access (OBDA)).  ... 
doi:10.18419/opus-9871 fatcat:pkfsusa32vekvgqslqkt2taoxu

Architecture for Accessing Heterogeneous Databases

Mohd Kamir Yusof, Ahmad Faisal Amri Abidin, Mohd Nordin Abdul Rahman
2012 International Journal of Information Technology and Computer Science  
This paper presents the architecture for accessing heterogeneous databases. Two major processes in this architecture which are extracting SQL statement and ontology.  ...  Ontology approach was implemented and combined with these algorithms. In ontology approach, web semantic was implemented in order to retrieve only relevant data from database.  ...  Build Ontology -Based Query (Extracting Wrapper Ontology) First step in implementation of ontology is to create a model for query relational database on ontology.  ... 
doi:10.5815/ijitcs.2012.01.04 fatcat:onjs6rdhkvh7hdvv2f62k3km2m

Access Control Model Based on RDB Security Policy for OWL Ontology [chapter]

Dongwon Jeong, Yixin Jing, Doo-Kwon Baik
2007 Lecture Notes in Computer Science  
The paper proposes a novel access control model for OWL ontologies in relational database systems. The access control is realized through evaluating queries against an OWL data view.  ...  Most of information has been storing and managing in relational databases and there are many researches to store OWL ontologies.  ...  There might be a question why we propose an access control model for OWL knowledge bases in relational databases.  ... 
doi:10.1007/978-3-540-72586-2_103 fatcat:zzpokemhmrc35mh7pkxfle5crm
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