Query-condition-aware V-optimal histogram in range query selectivity estimation
نویسندگان
چکیده
منابع مشابه
Query Selectivity Estimation Based on Improved V-optimal Histogram by Introducing Information about Distribution of Boundaries of Range Query Conditions
Selectivity estimation is a parameter used by a query optimizer for early estimation of the size of data that satisfies query condition. Selectivity is calculated using an estimator of distribution of attribute values of attribute involved in a processed query condition. Histograms built on attributes values from a database may be such representation of the distribution. The paper introduces a ...
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ژورنال
عنوان ژورنال: Bulletin of the Polish Academy of Sciences Technical Sciences
سال: 2014
ISSN: 2300-1917
DOI: 10.2478/bpasts-2014-0029