135 search results - page 18 / 27 » Answering aggregate keyword queries on relational databases ... |
CIKM
2010
Springer
13 years 5 months ago
2010
Springer
Schema merging is the process of consolidating multiple schemas into a unified view. The task becomes particularly challenging when the schemas are highly heterogeneous and autono...
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...
CCS
2007
ACM
14 years 1 months ago
2007
ACM
In this paper, we study the maintenance of role-based access control (RBAC) models in database environments using transitive closure relations. In particular, the algorithms that ...
WWW
2011
ACM
13 years 2 months ago
2011
ACM
The ability to aggregate huge volumes of queries over a large population of users allows search engines to build precise models for a variety of query-assistance features such as ...
CIKM
2005
Springer
14 years 1 months ago
2005
Springer
Despite the recent advances in search quality, the fast increase in the size of the Web collection has introduced new challenges for Web ranking algorithms. In fact, there are sti...