204 search results - page 3 / 41 » Containment of Conjunctive Queries with Negation: Algorithms... |
FOCS
1998
IEEE
13 years 10 months ago
1998
IEEE
This paper deals with the evaluation of acyclic Boolean conjunctive queries in relational databases. By well-known results of Yannakakis [1981], this problem is solvable in polynom...
IJCAI
2007
13 years 7 months ago
2007
Conjunctive queries play an important role as an expressive query language for Description Logics (DLs). Although modern DLs usually provide for transitive roles, conjunctive quer...
DLOG
2006
13 years 7 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...
BVAI
2007
Springer
13 years 12 months ago
2007
Springer
We tested the efficiency of category learning when participants are provided only with pairs of objects, known to belong either to the same class (Positive Equivalence Constraints ...
PODS
2011
ACM
12 years 8 months ago
2011
ACM
In deletion propagation, tuples from the database are deleted in order to reflect the deletion of a tuple from the view. Such an operation may result in the (often necessary) del...