342 search results - page 1 / 69 » Conjunctive Queries over Trees |
DBPL
2007
Springer
13 years 11 months ago
2007
Springer
Abstract. The complexity of containment and satisfiability of conjunctive queries over finite, unranked, labeled trees is studied with respect to the axes Child, NextSibling, the...
PODS
2004
ACM
14 years 4 months ago
2004
ACM
SEMWEB
2010
Springer
13 years 2 months ago
2010
Springer
Abstract. In order to effectively and quickly answer queries in environments with distributed RDF/OWL, we present a query optimization algorithm to identify the potentially relevan...
P2P
2006
IEEE
13 years 10 months ago
2006
IEEE
Peers in peer-to-peer file-sharing systems use conjunctive queries as a way of controlling query cost in the absence of information about the behavior of other peers. Conjunctive ...
ICDT
2007
ACM
13 years 11 months ago
2007
ACM
Abstract. We study containment of conjunctive queries that are evaluated over databases that may contain tuples with null values. We assume the semantics of SQL for single block qu...