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PVLDB
2008
122views more  PVLDB 2008»
13 years 12 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
ICDE
2007
IEEE
98views Database» more  ICDE 2007»
14 years 6 months ago
Towards Adaptive Costing of Database Access Methods
Most database query optimizers use cost models to identify good query execution plans. Inaccuracies in the cost models can cause query optimizers to select poor plans. In this pap...
Ye Qin, Kenneth Salem, Anil K. Goel