PVLDB
2010
13 years 2 months ago
2010
Virtual views are a mechanism that facilitates re-use and makes queries easier to express. However the use of iterative view definitions makes very simple query evaluation and an...
DEXA
2010
Springer
13 years 4 months ago
2010
Springer
We consider the containment problem for conjunctive queries with atomic negation. Firstly, we refine an existing algorithm based on homomorphism checks, which itself improves other...
TREC
2004
13 years 5 months ago
2004
Web search engines exploit conjunctive queries and special ranking criteria which differ from the disjunctive queries typically used for ad-hoc retrieval. We wanted to asses the e...
SEBD
2007
13 years 5 months ago
2007
The use of ontologies in various application domains, such as Data Integration, the Semantic Web, or ontology-based data management, where ontologies provide the access to large am...
AMW
2010
13 years 5 months ago
2010
We address the problem of answering conjunctive queries over knowledge bases, specified by sets of first-order sentences called tuple-generating dependencies (TGDs). This problem i...
DEXAW
2008
IEEE
13 years 6 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. In ...
DLOG
2008
13 years 6 months ago
2008
Answering conjunctive queries (CQs) has been recognized as a key task for the usage of Description Logics (DLs) in a number of applications. The problem has been studied by many au...
DLOG
2007
13 years 6 months ago
2007
We present cq-programs, which enhance nonmonotonic description logics (dl-) programs by conjunctive queries (CQ) and union of conjunctive queries (UCQ) over Description Logics kno...
AAAI
2007
13 years 6 months ago
2007
The use of ontologies in various application domains, such as Data Integration, the Semantic Web, or ontology-based data management, where ontologies provide the access to large a...
AAAI
2008
13 years 6 months ago
2008
Answering conjunctive queries (CQs) has been recognized as a key task for the usage of Description Logics (DLs) in a number of applications, and has thus been studied by many auth...