151 search results - page 2 / 31 » On the Containment Problem for Queries in Conjunctive Form w... |
ICDT
2009
ACM
14 years 8 months ago
2009
ACM
The class of unions of conjunctive queries (UCQ) has been shown to be particularly well-behaved for data exchange; its certain answers can be computed in polynomial time (in terms...
PODS
2000
ACM
13 years 12 months ago
2000
ACM
The problem of query containment is fundamental to many aspects of database systems, including query optimization, determining independence of queries from updates, and rewriting ...
PODS
2006
ACM
14 years 7 months ago
2006
ACM
Query containment is a fundamental algorithmic problem in database query processing and optimization. Under set semantics, the query-containment problem for conjunctive queries ha...
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 ...
ICDT
2007
ACM
14 years 1 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...