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» Monitoring Plan Optimality During Execution
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SSDBM
2005
IEEE
140views Database» more  SSDBM 2005»
14 years 1 months ago
Optimizing In-Order Execution of Continuous Queries over Streamed Sensor Data
The widespread use of sensor networks in scientific and engineering applications leads to increased demand on the efficient computation of the collected sensor data. Recent rese...
Moustafa A. Hammad, Walid G. Aref, Ahmed K. Elmaga...
PVLDB
2008
122views more  PVLDB 2008»
13 years 7 months ago
Identifying robust plans through plan diagram reduction
Estimates of predicate selectivities by database query optimizers often differ significantly from those actually encountered during query execution, leading to poor plan choices a...
Harish D., Pooja N. Darera, Jayant R. Haritsa
FUIN
2006
139views more  FUIN 2006»
13 years 7 months ago
Efficient Parallel Query Processing by Graph Ranking
In this paper we deal with the problem of finding an optimal query execution plan in database systems. We improve the analysis of a polynomial-time approximation algorithm due to M...
Dariusz Dereniowski, Marek Kubale
EDBTW
2006
Springer
13 years 11 months ago
Dynamic Plan Migration for Snapshot-Equivalent Continuous Queries in Data Stream Systems
A data stream management system executes a large number of continuous queries in parallel. As stream characteristics and query workload change over time, the plan initially install...
Jürgen Krämer, Yin Yang, Michael Cammert...
EDBT
2006
ACM
127views Database» more  EDBT 2006»
14 years 7 months ago
Progressive Query Optimization for Federated Queries
Federated queries are regular relational queries accessing data on one or more remote relational or non-relational data sources, possibly combining them with tables stored in the ...
Stephan Ewen, Holger Kache, Volker Markl, Vijaysha...