Title
Scheduling for shared window joins over data streams
Abstract
Continuous Query (CQ) systems typically exploit commonality among query expressions to achieve improved efficiency through shared processing. Recently proposed CQ systems have introduced window specifications in order to support unbounded data streams. There has been, however, little investigation of sharing for windowed query operators. In this paper, we address the shared execution of windowed joins, a core operator for CQ systems. We show that the strategy used in systems to date has a previously unreported performance flaw that can negatively impact queries with relatively small windows. We then propose two new execution strategies for shared joins. We evaluate the alternatives using both analytical models and implementation in a DBMS. The results show that one strategy, called MQT, provides the best performance over a range of workload settings.
Year
DOI
Venue
2003
10.1016/B978-012722442-8/50034-3
VLDB
Keywords
Field
DocType
windowed query operator,shared window,shared execution,shared processing,query expression,new execution strategy,continuous query,best performance,impact query,cq system,data stream,unreported performance flaw
Data stream mining,Joins,Expression (mathematics),Scheduling (computing),Computer science,Workload,Exploit,Operator (computer programming),Database,Distributed computing
Conference
ISSN
ISBN
Citations 
Proceedings 2003 VLDB Conference
0-12-722442-4
85
PageRank 
References 
Authors
4.79
14
4
Name
Order
Citations
PageRank
Moustafa A. Hammad129719.61
Michael J. Franklin2174231681.10
Walid G. Aref34502419.49
Ahmed K. Elmagarmid43720626.92