Selectivity and Cost Estimation for Joins Based on Random Sampling
نویسندگان
چکیده
منابع مشابه
Selectivity Estimation for Joins Using Systematic Sampling
We propose a new approach to the estimation of join selectivity. The technique, which we have called “systematic sampling”, is a novel variant of the sampling-based approach. Systematic sampling works as follows: Given a relation R of N tuples, with a join attribute that can be accessed in ascending/descending order via an index, if n is the number of tuples to be sampled from R, select a tuple...
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ژورنال
عنوان ژورنال: Journal of Computer and System Sciences
سال: 1996
ISSN: 0022-0000
DOI: 10.1006/jcss.1996.0041