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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  ...  In this paper we present a new approach to the optimization of query rewriting in OBDA.  ...  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

On Rewriting, Answering Queries in OBDA Systems for Big Data (Short Paper)

Diego Calvanese, Ian Horrocks, Ernesto Jiménez-Ruiz, Evgeny Kharlamov, Michael Meier, Mariano Rodriguez-Muro, Dmitriy Zheleznyakov
2013 W3C Web Ontology Language (OWL) Experiences and Directions Workshop (OWLED)  
The project Optiqueaims at providing an end-to-end solution for scalable access to Big Data integration, were end users will formulate queries based on a familiar conceptualization of the underlying domain  ...  From the users queries the Optique platform will automatically generate appropriate queries over the underlying integrated data, optimize and execute them.  ...  The approach, known as "Ontology-Based Data Access" (OBDA) [13, 2] , has the potential to address the data access problem by automating the translation process of the users information needs.  ... 
dblp:conf/owled/CalvaneseHJKMRZ13 fatcat:tysxybfoora2tbxnt3sn6dnfxa

Mastro Studio: a System for Ontology-Based Data Management

Domenico Lembo, Valerio Santarelli, Domenico Fabio Savo, Cristina Civili, Marco Console, Lorenzo Lepore, Riccardo Mancini, Antonella Poggi, Marco Ruzzi
2013 W3C Web Ontology Language (OWL) Experiences and Directions Workshop (OWLED)  
Introduction Ontology-based data access (OBDA) is a computing paradigm in which access to data is realized through a three-level architecture, constituted by an ontology, a set of data sources, and the  ...  ., the query rewriting, the consistency checking, and the intensional reasoning module. The query rewriting module realizes the query rewriting process and its optimizations described in Section 2.  ... 
dblp:conf/owled/LemboSSCCLMPR13 fatcat:u7xzaqmb7fb2tkw2s2e7j3vz7y

Practical Aspects of Query Rewriting for OWL 2

Héctor Pérez-Urbina, Ian Horrocks, Boris Motik
2009 International Semantic Web Conference  
In this paper, we describe query rewriting, briefly present the results of our empirical evaluation, and discuss various optimization techniques aimed at reducing the size of the rewritings.  ...  In order to test the likely practicality of RQR, we have implemented it in a query rewriting system that we call REQUIEM.  ...  Ontology-based Data Access via Query Rewriting We now describe how to answer queries posed over an OWL 2 QL ontology and a database using query rewriting.  ... 
dblp:conf/semweb/Perez-UrbinaHM08 fatcat:d7jfwmbagvfbhnj7e5pwsygzyu

Query optimization for ontology-based information integration

Yingjie Li, Jeff Heflin
2010 Proceedings of the 19th ACM international conference on Information and knowledge management - CIKM '10  
We present an algorithm that, given a set of query rewritings that accounts for ontology heterogeneity, incrementally selects and processes sources in order to maintain selectivity.  ...  In order to effectively and quickly answer queries in such an environment, we present an approach to identifying the potentially relevant Semantic Web data sources using query rewritings and a term index  ...  In Section 3, we describe the query optimization algorithm for ontology-based information integration using the term index.  ... 
doi:10.1145/1871437.1871623 dblp:conf/cikm/LiH10 fatcat:m5rwysmg5jbctosnrxvp7lgnt4

An Ontology-Based Framework for Heterogeneous Data Sources Integration

Vânia M. P. Vidal, João C. Pinheiro, Eveline R. Sacramento, José Antonio Fernandes de Macêdo, Bernadette F. Lóscio
2010 Revista de Informática Teórica e Aplicada  
, little work has been done focusing on the optimization of querying processing in a ontology-based data integration system.  ...  An important challenge in ontology-based data integration systems is the problem of rewriting a query specified in terms of the domain ontology into queries that can be answered by the individual data  ...  , little work has been done focusing on the optimization of querying processing in a ontology-based data integration system.  ... 
doi:10.22456/2175-2745.12570 fatcat:uuhj4gketnex5ntvcuz2eqtep4

Mastro studio

Cristina Civili, Marco Ruzzi, Valerio Santarelli, Domenico Fabio Savo, Marco Console, Giuseppe De Giacomo, Domenico Lembo, Maurizio Lenzerini, Lorenzo Lepore, Riccardo Mancini, Antonella Poggi, Riccardo Rosati
2013 Proceedings of the VLDB Endowment  
Ontology-based data access (OBDA) is a novel paradigm for accessing large data repositories through an ontology, that is a formal description of a domain of interest.  ...  To fulfill these challenges, we have built a novel system, called MASTRO STUDIO, based on a tool for automated reasoning over ontologies, enhanced with a suite of tools and optimization facilities for  ...  Research on OBDA, and in particular on mapping management, has been partially funded by the EU under FP7 project Optique -Scalable End-user Access to Big Data (grant n. FP7-318338).  ... 
doi:10.14778/2536274.2536304 fatcat:eqi2daimh5bbrcfp7too5wejbm

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

Diego Calvanese, Manolis Koubarakis, David Toman
2015 Journal of Web Semantics  
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.  ...  The aim of an OBDA system is to answer user queries by transforming them into appropriate queries to the data layer, using the ontology and the mapping.  ...  experience derived from practical deployments of OBDA components to support access to real-world data sets in daily use.  ... 
doi:10.1016/j.websem.2015.06.001 fatcat:uqfd6zdr7vayvei2ylpuy7lzhy

Quest, an OWL 2 QL Reasoner for Ontology-based Data Access

Mariano Rodriguez-Muro, Diego Calvanese
2012 W3C Web Ontology Language (OWL) Experiences and Directions Workshop (OWLED)  
In such configuration all data remains in the data source and is only accessed at run-time. Quest uses query rewriting techniques as the inference mechanism in both modes.  ...  Ontology Based Data Access (OBDA) has drawn considerable attention from the OWL and RDF communities.  ...  At the same time, the terminological part of an ontology (the TBox) allows for obtaining richer answers by means of OWL and RDFS inference. This scenario is called Ontology Based Data Access (OBDA).  ... 
dblp:conf/owled/Rodriguez-MuroC12 fatcat:dj4sbp4qz5crbgohd5hs63gdsu

Using Reformulation Trees to Optimize Queries over Distributed Heterogeneous Sources [chapter]

Yingjie Li, Jeff Heflin
2010 Lecture Notes in Computer Science  
In order to effectively and quickly answer queries in environments with distributed RDF/OWL, we present a query optimization algorithm to identify the potentially relevant Semantic Web data sources using  ...  This algorithm is based on the observation that the join selectivity of a pair of query triple patterns is often higher than the overall selectivity of these two patterns treated independently.  ...  However, when there is significant heterogeneity in the ontologies, synonymous ontology expressions can lead to an explosion in the number of query rewrites.  ... 
doi:10.1007/978-3-642-17746-0_32 fatcat:ji2lb3h42nchjbqfwjs5usxfj4

Ontology-Based Data Access Using Views [chapter]

Juan F. Sequeda, Marcelo Arenas, Daniel P. Miranker
2012 Lecture Notes in Computer Science  
In this paper, we propose a new approach to answering SPARQL queries on OWL 2 QL ontologies over existing relationally stored data.  ...  Unfortunately, given a query Q posed in terms of an OWL 2 QL ontology 1 O, the size of the rewritten query, Q o , which can be evaluated directly on the relational database, is worst case exponential w.r.t  ...  The Status Quo The status quo of systems that answer queries over an OWL 2 QL ontology mapped to a relational database, also known as Ontology-based Data Access (OBDA), consists of the following input:  ... 
doi:10.1007/978-3-642-33203-6_29 fatcat:wtnrn5q6d5bejosjd66cyln4em

Efficient Query Answering for OWL 2 [chapter]

Héctor Pérez-Urbina, Ian Horrocks, Boris Motik
2009 Lecture Notes in Computer Science  
We present a comparison of our resolution based rewriting algorithm with the standard algorithm proposed by Calvanese et al., implementing both and conducting an empirical evaluation using ontologies and  ...  The QL profile of OWL 2 has been designed so that it is possible to use database technology for query answering via query rewriting.  ...  developed for ontology-based data access [10] .  ... 
doi:10.1007/978-3-642-04930-9_31 fatcat:rxbnpnhfrjfujm3oz3sir6obxm

Mastro: Ontology-Based Data Access at Work (Extended Abstract) [chapter]

Giuseppe De Giacomo, Domenico Lembo, Maurizio Lenzerini, Antonella Poggi, Riccardo Rosati, Marco Ruzzi, Domenico Fabio Savo
2012 Lecture Notes in Computer Science  
Mastro allows users for accessing external data sources by querying an ontology expressed in a fragment of the W3C Web Ontology Language (OWL).  ...  This is also by virtue of novel optimization techniques that exploit containment relationships between queries generated at the rewriting steps in order to reduce the size of the final SQL query.  ... 
doi:10.1007/978-3-642-33618-8_90 fatcat:c6rl7cin4vbfxoi4vaflgjgzhi

Ontology-Based Data Access: The Experience at the Italian Department of Treasury

Natalia Antonioli, Francesco Castanò, Cristina Civili, Spartaco Coletta, Stefano Grossi, Domenico Lembo, Maurizio Lenzerini, Antonella Poggi, Domenico Fabio Savo, Emanuela Virardi
2013 International Conference on Advanced Information Systems Engineering  
Ontology-based data access (OBDA) is a new paradigm for managing complex information systems through semantic technologies.  ...  After illustrating the state of the art of ODBA research at the beginning of the project, we describe the various steps we have carried out in order to apply the research results in a real-world settings  ...  The research on OBDA, and in particular on mapping management, at the basis of the experience described in this paper has been partially funded by the EU under FP7 project Optique -Scalable End-user Access  ... 
dblp:conf/caise/AntonioliCCCGLLPSV13 fatcat:zgop2vt2grfcbbhlobkgo3fjzy

Querying Rich Ontologies by Exploiting the Structure of Data

Labinot Bajraktari
2020 Künstliche Intelligenz  
Ontology-based data access (OBDA) has emerged as a paradigm for accessing heterogeneous and incomplete data sources.  ...  In the dissertation, a technique that leverages the structural properties of data to help alleviate the problems that typically arise when answering the queries in expressive settings is developed.  ...  To view a copy of this licence, visit http://creat iveco mmons .org/licen ses/by/4.0/.  ... 
doi:10.1007/s13218-020-00672-9 dblp:journals/ki/Bajraktari20 fatcat:jnntlocoojaenm4xxk4ym7w74u
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