Sciweavers

SIGMOD
1996
ACM
97views Database» more  SIGMOD 1996»
13 years 9 months ago
Bifocal Sampling for Skew-Resistant Join Size Estimation
This paper introduces bifocal sampling, a new technique for estimating the size of an equi-join of two relations. Bifocal sampling classi es tuples in each relation into two group...
Sumit Ganguly, Phillip B. Gibbons, Yossi Matias, A...
PODS
1999
ACM
121views Database» more  PODS 1999»
13 years 9 months ago
Tracking Join and Self-Join Sizes in Limited Storage
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...
Noga Alon, Phillip B. Gibbons, Yossi Matias, Mario...