204 search results - page 21 / 41 » Containment of Conjunctive Queries with Negation: Algorithms... |
DEXA
2008
Springer
13 years 10 months ago
2008
Springer
The paper presents a novel method for compressing large database workloads for purpose of autonomic, continuous index selection. The compressed workload contains a small subset of ...
VLDB
2002
ACM
13 years 8 months ago
2002
ACM
Traditional indexes aim at optimizing the node accesses during query processing, which, however, does not necessarily minimize the total cost due to the possibly large number of r...
SIGMOD
2007
ACM
14 years 9 months ago
2007
ACM
Complex queries often contain common or similar subexpressions, either within a single query or among multiple queries submitted as a batch. If so, query execution time can be imp...
IPPS
2005
IEEE
14 years 2 months ago
2005
IEEE
Continuous query systems are an intuitive way for users to access streaming data in large-scale scientific applications containing many hundreds of streams. A challenge in these ...
WWW
2010
ACM
14 years 4 months ago
2010
ACM
Today the major web search engines answer queries by showing ten result snippets, which need to be inspected by users for identifying relevant results. In this paper we investigat...