A Semantic Web Middleware for Virtual Data Integration on the Web
A Semantic Web Middleware for Virtual Data Integration on the Web | |
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A Semantic Web Middleware for Virtual Data Integration on the Web
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Bibliographical Metadata | |
Subject: | Querying Distributed RDF Data Sources |
Year: | 2008 |
Authors: | Andreas Langegger, Wolfram Wöß, Martin Blochl |
Venue | ESWC |
Content Metadata | |
Problem: | SPARQL Query Federation |
Approach: | Querying Distributed RDF Data Sources |
Implementation: | SemWIQ |
Evaluation: | No data available now. |
Contents
Abstract
In this contribution a system is presented, which provides access to distributed data sources using Semantic Web technology. While it was primarily designed for data sharing and scientific collaboration, it is regarded as a base technology useful for many other Semantic Web applications. The proposed system allows to retrieve data using SPARQL queries, data sources can register and abandon freely, and all RDF Schema or OWL vocabularies can be used to describe their data, as long as they are accessible on the Web. Data heterogeneity is addressed by RDF-wrappers like D2R-Server placed on top of local information systems. A query does not directly refer to actual endpoints, instead it contains graph patterns adhering to a virtual data set. A mediator finally pulls and joins RDF data from different endpoints providing a transparent on-the-fly view to the end-user. The SPARQL protocol has been defined to enable systematic data access to remote endpoints. However, remote SPARQL queries require the explicit notion of endpoint URIs. The presented system allows users to execute queries without the need to specify target endpoints. Additionally, it is possible to execute join and union operations across different remote endpoints. The optimization of such distributed operations is a key factor concerning the performance of the overall system. Therefore, proven concepts from database research can be applied.
Conclusion
In this contribution a mediator-based system for virtual data integration based on SemanticWeb technology has been presented. The system is primarily developed for sharing scientific data, but because of its generic architecture, it is supposed to be used for many other Semantic Web applications. In this paper query federation based on SPARQL and Jena/ARQ has been demonstrated in detail and several concepts for query optimization which is currently on the agenda have been discussed. Additional contributions can be expected after the implementation of additional features mentioned before.
Future work
Approach
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Requirements: {{{Requirements}}}
Limitations: {{{Limitations}}}
Implementations
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GUI: No
Research Problem
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Evaluation
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Access API | {{{API}}} + |
Event in series | ESWC + |
Has Challenges | {{{Challenges}}} + |
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Has Description | {{{Description}}} + |
Has Dimensions | {{{Dimensions}}} + |
Has DocumentationURL | http://{{{DocumentationURL}}} + |
Has Downloadpage | http://{{{Download-page}}} + |
Has Evaluation | No data available now. + |
Has EvaluationMethod | {{{EvaluationMethod}}} + |
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Has GUI | No + |
Has Hypothesis | {{{Hypothesis}}} + |
Has Implementation | SemWIQ + |
Has InfoRepresentation | {{{InfoRepresentation}}} + |
Has Limitations | {{{Limitations}}} + |
Has NegativeAspects | {{{NegativeAspects}}} + |
Has PositiveAspects | {{{PositiveAspects}}} + |
Has Requirements | {{{Requirements}}} + |
Has Results | {{{Results}}} + |
Has Version | {{{Version}}} + |
Has abstract | In this contribution a system is presented … In this contribution a system is presented, which provides access to distributed data sources using Semantic Web technology. While it was primarily designed for data sharing and scientific collaboration, it is regarded as a base technology useful for many other Semantic Web applications. The proposed system allows to retrieve data using SPARQL queries, data sources can register and abandon freely, and all RDF Schema or OWL vocabularies can be used to describe their data, as long as they are accessible on the Web. Data heterogeneity is addressed by RDF-wrappers like D2R-Server placed on top of local information systems. A query does not directly refer to actual endpoints, instead it contains graph patterns adhering to a virtual data set. A mediator finally pulls and joins RDF data from different endpoints providing a transparent on-the-fly view to the end-user. The SPARQL protocol has been defined to enable systematic data access to remote endpoints. However, remote SPARQL queries require the explicit notion of endpoint URIs. The presented system allows users to execute queries without the need to specify target endpoints. Additionally, it is possible to execute join and union operations across different remote endpoints. The optimization of such distributed operations is a key factor concerning the performance of the overall system. Therefore, proven concepts from database research can be applied. pts from database research can be applied. + |
Has approach | Querying Distributed RDF Data Sources + |
Has authors | Andreas Langegger +, Wolfram Wöß + and Martin Blochl + |
Has conclusion | In this contribution a mediator-based syst … In this contribution a mediator-based system for virtual data integration based on SemanticWeb technology has been presented. The system is primarily developed for sharing scientific data, but because of its generic architecture, it is supposed to be used for many other Semantic Web applications. In this paper query federation based on SPARQL and Jena/ARQ has been demonstrated in detail and several concepts for query optimization which is currently on the agenda have been discussed. Additional contributions can be expected after the implementation of additional features mentioned before. n of additional features mentioned before. + |
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Has problem | SPARQL Query Federation + |
Has subject | Querying Distributed RDF Data Sources + |
Has vendor | {{{vendor}}} + |
Has year | 2008 + |
Proposes Algorithm | {{{ProposesAlgorithm}}} + |
Title | A Semantic Web Middleware for Virtual Data Integration on the Web + |
Uses Framework | {{{Framework}}} + |
Uses Methodology | {{{Methodology}}} + |
Uses Toolbox | {{{Toolbox}}} + |