121 search results - page 7 / 25 » On Containment of Conjunctive Queries with Negation |
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...
DEDUCTIVE
1994
13 years 9 months ago
1994
Given an intensional database (IDB) and an extension database (EDB), the view update problem translates updates on the IDB into updates on the EDB. One approach to the view update...
PODS
2004
ACM
14 years 7 months ago
2004
ACM
We study the problem of answering queries over sources with limited access patterns. Given a first-order query Q, the problem is to decide whether there is an equivalent query whi...
ICFCA
2007
Springer
14 years 1 months ago
2007
Springer
We model a Digital Library as a formal context in which objects are documents and attributes are terms describing documents contents. A formal concept is very close to the notion o...
DLOG
2006
13 years 9 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...