418 search results - page 9 / 84 » Optimizing Large Join Queries in Mediation Systems |
ICDE
2009
IEEE
14 years 2 months ago
2009
IEEE
— Complex ad hoc join queries over enterprise databases are commonly used by business data analysts to understand and analyze a variety of enterprise-wide processes. However, eff...
ICDE
2001
IEEE
14 years 9 months ago
2001
IEEE
Semi-join reducers were introduced in the late seventies as a means to reduce the communication costs of distributed database systems. Subsequent work in the eighties showed, howe...
ICDE
2002
IEEE
2002
IEEE
Design and Evaluation of Alternative Selection Placement Strategies in Optimizing Continuous Queries
14 years 9 months ago
In this paper, we design and evaluate alternative selection placement strategies for optimizing a very large number of continuous queries in an Internet environment. Two grouping ...
VLDB
2004
ACM
14 years 7 months ago
2004
ACM
Ranking queries produce results that are ordered on some computed score. Typically, these queries involve joins, where users are usually interested only in the top-k join results....
PODS
1999
ACM
13 years 12 months ago
1999
ACM
Query optimizers rely on fast, high-quality estimates of result sizes in order to select between various join plans. Selfjoin sizes of relations provide bounds on the join size of...