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https://issues.apache.org/jira/browse/HIVE-22239?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Jesus Camacho Rodriguez reassigned HIVE-22239:
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> Scale data size using column value ranges
> -----------------------------------------
>
>                 Key: HIVE-22239
>                 URL: https://issues.apache.org/jira/browse/HIVE-22239
>             Project: Hive
>          Issue Type: Improvement
>          Components: Physical Optimizer
>            Reporter: Jesus Camacho Rodriguez
>            Assignee: Jesus Camacho Rodriguez
>            Priority: Major
>
> Currently, min/max values for columns are only used to determine whether a 
> certain range filter falls out of range and thus filters all rows or none at 
> all. If it does not, we just use a heuristic that the condition will filter 
> 1/3 of the input rows. Instead of using that heuristic, we can use another 
> one that assumes that data will be uniformly distributed across that range, 
> and calculate the selectivity for the condition accordingly.
> This patch also includes the propagation of min/max column values from 
> statistics to the optimizer for timestamp type.



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