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Semantics and Complexity of SPARQL [article]

Jorge Perez, Marcelo Arenas, Claudio Gutierrez
2006 arXiv   pre-print
We provide a compositional semantics, prove there are normal forms, prove complexity bounds, among others that the evaluation of SPARQL patterns is PSPACE-complete, compare our semantics to an alternative  ...  operational semantics, give simple and natural conditions when both semantics coincide and discuss optimizations procedures.  ...  Although taken one by one the features of SPARQL are simple to describe and understand, it turns out that the combination of them makes SPARQL into a complex language, whose semantics is far from being  ... 
arXiv:cs/0605124v1 fatcat:ww4sb6bzlfcoximbb4qx5p4bze

Semantics and complexity of SPARQL

Jorge Pérez, Marcelo Arenas, Claudio Gutierrez
2009 ACM Transactions on Database Systems  
We provide a compositional semantics for the core part of SPARQL, and study the complexity of the evaluation of several fragments of the language.  ...  Organization of the Article. Section 2 presents a formalized algebraic syntax and a compositional semantics for SPARQL. Section 3 presents the complexity study of the language.  ...  ACKNOWLEDGMENTS We are grateful to the anonymous referees for their careful reading of the article, and for providing many useful comments. We would also like to thank M.  ... 
doi:10.1145/1567274.1567278 fatcat:f5qdvjxvlncahixa34s2v2pkqe

Semantics and Complexity of SPARQL [chapter]

Jorge Pérez, Marcelo Arenas, Claudio Gutierrez
2006 Lecture Notes in Computer Science  
We provide a compositional semantics, prove there are normal forms, prove complexity bounds, among others that the evaluation of SPARQL patterns is PSPACE-complete, compare our semantics to an alternative  ...  operational semantics, give simple and natural conditions when both semantics coincide and discuss optimizations procedures.  ...  Although taken one by one the features of SPARQL are simple to describe and understand, it turns out that the combination of them makes SPARQL into a complex language, whose semantics is far from being  ... 
doi:10.1007/11926078_3 fatcat:w2lx2pkw6fhu3mcxwyedlkscda

An RDF Vocabulary for Meta-Programming with SPARQL Algebra

Miguel Ceriani, Alejandro A. Vaisman
2016 Alberto Mendelzon Workshop on Foundations of Data Management  
The representation used so far, SPIN SPARQL, closely follows the abstract syntax tree, but fails to directly capture the semantics and is hard to work with for query rewriting.  ...  Here a novel vocabulary based on SPARQL Algebra is presented. The adequacy of the language is empirically shown through a few examples.  ...  Similar rules would be hard to write from SPIN SPARQL, unless preceded by a complex set of rules that modify the syntax tree to reflect the semantics (thus realizing in a way the conversion to SPARQL Algebra  ... 
dblp:conf/amw/CerianiV16 fatcat:laqfbkr6qvd2dkbzb3ixspyfue

Semantic Processing of Sensor Event Stream by Using External Knowledge Bases (Short Paper)

Kia Teymourian, Adrian Paschke
2012 International Semantic Web Conference  
Usage of domain background knowledge about sensor data can improve the expressiveness and flexibility of event processing in sensor network applications.  ...  In this paper, we discuss the benefits of background knowledge for event processing and describe a simple classification of event query rules. 1  ...  The semantics of the whole event query is a hybrid semantic of description logic and event operation algebra which defines the semantics of event detection.  ... 
dblp:conf/semweb/TeymourianP12 fatcat:4s4d3vfgirhk5nigcg25lkjaby

Enabling knowledge-based complex event processing

Kia Teymourian, Adrian Paschke
2010 Proceedings of the 1st International Workshop on Data Semantics - DataSem '10  
understand the semantics of events.  ...  Usage of background knowledge about events and their relations to other concepts in the application domain can improve the expressiveness and flexibility of complex event processing systems.  ...  EP-SPARQL [1] is a language for complex events and stream reasoning. The formal semantics of EP-SPARQL is along the same lines as SPARQL.  ... 
doi:10.1145/1754239.1754281 dblp:conf/edbtw/TeymourianP10 fatcat:hhbzpi2hnje77l4x7rjf2ub3li

Counting beyond a Yottabyte, or how SPARQL 1.1 property paths will prevent adoption of the standard

Marcelo Arenas, Sebastián Conca, Jorge Pérez
2012 Proceedings of the 21st international conference on World Wide Web - WWW '12  
To formally explain this fact, we conduct a theoretical study of the computational complexity of property paths evaluation.  ...  We provide several intractability results, that together with our empirical results, provide strong evidence against the current semantics of SPARQL 1.1 property paths.  ...  Acknowledgments Arenas was supported by Fondecyt-1090565, and Pérez by Fondecyt-11110404 and by VID grant U-Inicia 11/04, Universidad de Chile.  ... 
doi:10.1145/2187836.2187922 dblp:conf/www/ArenasCP12 fatcat:wpjfcgedpnfynjjvovhxljwbiy

Federation and Navigation in SPARQL 1.1 [chapter]

Marcelo Arenas, Jorge Pérez
2012 Lecture Notes in Computer Science  
We first introduce the SPARQL standard presenting its syntax and formal semantics. We then focus on the formalization of federation and navigation in SPARQL 1.1.  ...  Moreover, we present some important recently discovered issues regarding the normative semantics of federation and navigation in SPARQL 1.1, specifically, on the impossibility of answering some unbounded  ...  Notice that in these three problems, we are considering the data complexity of SPARQL 1.1 under the respective semantics.  ... 
doi:10.1007/978-3-642-33158-9_3 fatcat:vtnu3llk3naf7kivy3bz3orn5y

On the Semantics of SPARQL [chapter]

Marcelo Arenas, Claudio Gutierrez, Jorge Pérez
2009 Semantic Web Information Management  
We start by focusing on the definition of a formal semantics for the core part of SPARQL, and then move to the definition for the entire language, including all the features in the specification of SPARQL  ...  In this chapter, we give a detailed description of the semantics of SPARQL.  ...  On the Semantics of SPARQL 7 On the Semantics of SPARQL On the Semantics of SPARQL On the Semantics of SPARQL On the Semantics of SPARQL On the Semantics of SPARQL On  ... 
doi:10.1007/978-3-642-04329-1_13 fatcat:56k5t5j6tzdqzimyyrqz3p4izm

Imprecise SPARQL: Towards a Unified Framework for Similarity-Based Semantic Web Tasks

Christoph Kiefer
2007 Extended Semantic Web Conference  
We present some research questions, summarize the experimental work conducted so far, and present our research plan that focuses on the various challenges of similarity querying within the Semantic Web  ...  This proposal explores a unified framework to solve Semantic Web tasks that often require similarity measures, such as RDF retrieval, ontology alignment, and semantic service matchmaking.  ...  in ARQ. 1 -The semantics and complexity of UDSF-extended SPARQL queries are unclear.  ... 
dblp:conf/esws/Kiefer07 fatcat:l7fq4dr44zd4fnairmhowzqjtu

SPARQL-to-SQL Query Translation: Bottom-Up or Top-Down?

Andrey Kashlev, Artem Chebotko
2011 2011 IEEE International Conference on Services Computing  
Many existing semantic data repositories use conventional relational databases to store and query large RDF datasets. The most complex component of this approach is SPARQL-to-SQL query translation.  ...  To address this question, we study bottom-up and top-down translations of SPARQL queries with complex nested optional graph patterns that yield SQL queries with left outer joins whose reordering is not  ...  SPARQL-to-SQL translation is not only the most complex mapping in a relational RDF database, but also very critical to overall querying performance.  ... 
doi:10.1109/scc.2011.79 dblp:conf/IEEEscc/KashlevC11 fatcat:q3nw2hfezffktie5kexdwde2rq

SP-ACT: A hybrid framework for complex activity recognition combining OWL and SPARQL rules

Georgios Meditskos, Stamatia Dasiopoulou, Vasiliki Efstathiou, Ioannis Kompatsiaris
2013 2013 IEEE International Conference on Pervasive Computing and Communications Workshops (PERCOM Workshops)  
More specifically, the native semantics of OWL is used to formally represent and integrate activity-related information originated from different data sources, whereas SPARQL (SPIN) rules further aggregate  ...  In this paper we describe SP-ACT, a hybrid framework for the derivation of high-level activity interpretations in context-aware environments, by defining a combination of OWL ontologies and SPARQL CONSTRUCT  ...  ACKNOWLEDGMENT This work has been supported by the EU FP7 project Dem@Care: Dementia Ambient Care -Multi-Sensing Monitoring for Intelligent Remote Management and Decision Support under contract No. 288199  ... 
doi:10.1109/percomw.2013.6529451 dblp:conf/percom/MeditskosDEK13 fatcat:csofyz62drgdtemtlzox4udomu

Open Data Consumption Through the Generation of Disposable Web APIs

Paloma Caceres Garcia De Marina, Jose Maria Cavero Barca, Carlos E. Cuesta, Miguel Angel Garrido, Irene Garrigos, Cesar Gonzalez-Mora, Jose-Norberto Mazon, Almudena Sierra-Alonso, Belen Vela, Jose Jacobo Zubcoff
2021 IEEE Access  
open data in a situational scenario, thus avoiding the complexity and learning curve of SPARQL and the effort of manually processing the data.  ...  The ever-growing amount of information in today's world has led to the publication of more and more open data, i.e., that which is available in a free and reusable manner, on the Web.  ...  We used a two-factor ANOVA with interaction to analyze the effect on the response time for each type of tool (API/SPARQL) and the complexity (simple/complex).  ... 
doi:10.1109/access.2021.3082182 fatcat:l7g5yzj5izdd3ge5pmvr7fzl4e

SPARQL-RW

Konstantinos Makris, Nikos Bikakis, Nektarios Gioldasis, Stavros Christodoulakis
2012 Proceedings of the 15th International Conference on Extending Database Technology - EDBT '12  
To this end, it supports a set of rich and flexible mapping types and it is proved to provide semantics preserving queries.  ...  The SPARQL-RW provides a generic method for SPARQL query rewriting, with respect to a set of predefined mappings between ontology schemas.  ...  A SPARQL graph pattern consists of triple patterns, filters and SPARQL operators.  ... 
doi:10.1145/2247596.2247678 dblp:conf/edbt/MakrisBGC12 fatcat:ytqddqjuqzg5doc7bp4uvvgzma

Semantic Based Access over XML Data [chapter]

Nikos Bikakis, Nektarios Gioldasis, Chrisa Tsinaraki, Stavros Christodoulakis
2009 Lecture Notes in Computer Science  
The need for semantic processing of information and services has lead to the introduction of tools for the description and management of knowledge within organizations, such as RDF, OWL, and SPARQL.  ...  In this paper we describe the SPARQL2XQuery framework, which translates the SPARQL queries to semantically equivalent XQuery queries for accessing XML databases from the Semantic Web environment.  ...  , and O Object Property corresponds to XS Complex Element.  ... 
doi:10.1007/978-3-642-04754-1_27 fatcat:wwu2ahis4jhzjiqcl32ic4avju
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