143 search results - page 12 / 29 » Query Order and the Polynomial Hierarchy |
IEICET
2008
14 years 9 months ago
2008
We consider the polynomial time learnability of finite unions of ordered tree patterns with internal structured variables, in the query learning model of Angluin (1988). An ordered...
DEDUCTIVE
1994
14 years 10 months ago
1994
Non-deterministic operators are needed in First-Order relational languages and Datalog to extend the expressive power of such languages and support efficient formulations of lowco...
100
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ICIW
2008
IEEE
15 years 3 months ago
2008
IEEE
—With the increasing development of real applications using Semantic Web Technologies, it is necessary to provide scalable and efficient ontology querying and reasoning systems....
138
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SIGMOD
2007
ACM
15 years 9 months ago
2007
ACM
Dataspaces are collections of heterogeneous and partially unstructured data. Unlike data-integration systems that also offer uniform access to heterogeneous data sources, dataspac...
WWW
2005
ACM
15 years 10 months ago
2005
ACM
Some recent initiatives try to take profit from RDF to make XML documents interoperate at the semantic level. Ontologies are used to establish semantic connections among XML langu...