126 search results - page 18 / 26 » The Complexity of Acyclic Conjunctive Queries |
EDBT
2006
ACM
14 years 7 months ago
2006
ACM
In this paper we present a novel approach for estimating the selectivity of XML twig queries. Such a technique is useful for approximate query answering as well as for determining...
ASP
2003
Springer
14 years 23 days ago
2003
Springer
Default logic is used to describe regular behavior and normal properties. We suggest to exploit the framework of default logic for detecting outliers - individuals who behave in a...
COMGEO
2010
ACM
13 years 7 months ago
2010
ACM
We study the complexity and the I/O-efficient computation of flow on triangulated terrains. We present an acyclic graph, the descent graph, that enables us to trace flow paths in ...
ECAI
1994
Springer
13 years 11 months ago
1994
Springer
Abstract. Many recent works point out that there are several possibilities of assigning a meaning to a concept definition containing some sort of recursion. In this paper, we argue...
PVLDB
2010
13 years 6 months ago
2010
Ontology-based data access is a powerful form of extending database technology, where a classical extensional database (EDB) is enhanced by an ontology that generates new intensio...