126 search results - page 6 / 26 » The Complexity of Acyclic Conjunctive Queries |
LPAR
2007
Springer
14 years 1 months ago
2007
Springer
We study the data complexity of instance checking and conjunctive query answering in the EL family of description logics, with a particular emphasis on the boundary of tractability...
AAAI
2008
13 years 9 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...
DBPL
2001
Springer
14 years 9 hour ago
2001
Springer
Abstract. We are interested in the theoretical foundations of the optimization of conjunctive regular path queries (CRPQs). The basic problem here is deciding query containment bot...
ICDT
2007
ACM
14 years 1 months ago
2007
ACM
Query containment is a fundamental problem of databases. Given two queries q1 and q2, it asks whether the set of answers to q1 is included in the set of answers to q2 for any datab...
AMW
2010
13 years 9 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...