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On Provenance of Queries on Semantic Web Data
Found in: IEEE Internet Computing
By Yannis Theoharis, Irini Fundulaki, Grigoris Karvounarakis, Vassilis Christophides
Issue Date:January 2011
pp. 31-39
Capturing trustworthiness, reputation, and reliability of Semantic Web data manipulated by SPARQL requires researchers to represent adequate provenance information, usually modeled as source data annotations and propagated to query results along with a que...
Collaborative data sharing via update exchange and provenance
Found in: ACM Transactions on Database Systems (TODS)
By Grigoris Karvounarakis, Todd J. Green, Val Tannen, Zachary G. Ives
Issue Date:August 2013
pp. 1-42
Recent work [Ives et al. 2005] proposed a new class of systems for supporting data sharing among scientific and other collaborations: this new collaborative data sharing system connects heterogeneous logical peers using a network of schema mappings. Each p...
Algebraic structures for capturing the provenance of SPARQL queries
Found in: Proceedings of the 16th International Conference on Database Theory (ICDT '13)
By Floris Geerts, Grigoris Karvounarakis, Irini Fundulaki, Vassilis Christophides
Issue Date:March 2013
pp. 153-164
We show that the evaluation of SPARQL algebra queries on various notions of annotated RDF graphs can be seen as particular cases of the evaluation of these queries on RDF graphs annotated with elements of so-called spm-semirings. Spm-semirings extend semir...
Provenance semirings
Found in: Proceedings of the twenty-sixth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems (PODS '07)
By Grigoris Karvounarakis, Todd J. Green, Val Tannen
Issue Date:June 2007
pp. 31-40
We show that relational algebra calculations for incomplete databases, probabilistic databases, bag semantics and why-provenance are particular cases of the same general algorithms involving semirings. This further suggests a comprehensive provenance repre...
ORCHESTRA: facilitating collaborative data sharing
Found in: Proceedings of the 2007 ACM SIGMOD international conference on Management of data (SIGMOD '07)
By Grigoris Karvounarakis, Nicholas E. Taylor, Olivier Biton, Todd J. Green, Val Tannen, Zachary G. Ives
Issue Date:June 2007
pp. 1131-1133
Mashup Feeds is a system that supports integrated web service feeds as continuous queries. We introduce collection-based stream processing semantics to enable information extraction by monitoring source evolution over time.