Understanding cardinality estimation using entropy maximization
نویسندگان
چکیده
منابع مشابه
A Understanding Cardinality Estimation using Entropy Maximization
Cardinality estimation is the process of estimating the number of tuples returned by a query. In relational database query optimization, cardinality estimates are key statistics used by the optimizer to choose an (expected) lowest cost plan. As a result of the importance of the problem, there are many sources of statistical information available to the optimizer, e.g., query feedback records [S...
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ژورنال
عنوان ژورنال: ACM Transactions on Database Systems
سال: 2012
ISSN: 0362-5915,1557-4644
DOI: 10.1145/2109196.2109202