127 search results - page 4 / 26 » Conjunctive Query Containment under Access Limitations |
DLOG
2006
13 years 11 months ago
2006
The novel context of accessing and querying large data repositories through ontologies that are formalized in terms of expressive DLs requires on the one hand to consider query an...
ALT
2000
Springer
14 years 2 months ago
2000
Springer
A conjunctive query problem in relational database theory is a problem to determine whether or not a tuple belongs to the answer of a conjunctive query over a database. Here, a tup...
PODS
2006
ACM
14 years 10 months ago
2006
ACM
d Abstract] Guizhen Yang Artificial Intelligence Center SRI International Menlo Park, CA 94025, USA Michael Kifer Dept. of Computer Science Stony Brook University Stony Brook, NY 1...
ICDT
2005
ACM
14 years 3 months ago
2005
ACM
We study the problem of rewriting queries using views in the presence of access patterns, integrity constraints, disjunction, and negation. We provide asymptotically optimal algori...
ICDT
2009
ACM
14 years 10 months ago
2009
ACM
We study the problem of querying data sources that accept only a limited set of queries, such as sources accessible by Web services which can implement very large (potentially inf...