126 search results - page 4 / 26 » The Complexity of Acyclic Conjunctive Queries |
IJCAI
2007
13 years 9 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...
ADBIS
2009
Springer
14 years 2 months ago
2009
Springer
Abstract. We consider the problem of query containment for conjunctive queries with the safe negation property. Some necessary conditions for this problem are given. A part of the ...
DLOG
2007
13 years 9 months ago
2007
Abstract. Conjunctive query answering is an important DL reasoning task. Although this task is by now quite well-understood, tight complexity bounds for conjunctive query answering...
EDBT
2004
ACM
14 years 7 months ago
2004
ACM
We study the problem of answering queries over sources with limited access patterns. The problem is to decide whether a given query Q is feasible, i.e., equivalent to an executable...
SEBD
2007
13 years 9 months ago
2007
We consider the problem of query containment over an object data model derived from F-logic. F-logic has generated considerable interest commercially, in the academia, and within ...