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https://issues.apache.org/jira/browse/HIVE-29424?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Thomas Rebele updated HIVE-29424:
---------------------------------
    Description: 
Similar to HIVE-29364: the CBO planner should use the histogram statistics to 
estimate the selectivity of predicates such as
 * {{cast(b as BIGINT) < 6}}
 * {{cast(g as timestamp) >= "2020-11-7 00:00:00"}}
 * {{cast(g as timestamp) BETWEEN "2020-11-01 00:00:00" AND "2020-11-06 
00:00:00"}}

The hint of HIVE-29364 should be taken into account: if the CAST throws away 
information, the histogram statistics should not be used. E.g., {{{}CAST(128 as 
TINYINT) = -128{}}}, so a {{CAST(intField as TINYINT) > 42}} should not be 
treated the same as {{{}intField > 42{}}}, if the intField is outside of the 
range of TINYINT.

> CBO plans should use histogram statistics for range predicates with a CAST
> --------------------------------------------------------------------------
>
>                 Key: HIVE-29424
>                 URL: https://issues.apache.org/jira/browse/HIVE-29424
>             Project: Hive
>          Issue Type: Improvement
>            Reporter: Thomas Rebele
>            Assignee: Thomas Rebele
>            Priority: Major
>
> Similar to HIVE-29364: the CBO planner should use the histogram statistics to 
> estimate the selectivity of predicates such as
>  * {{cast(b as BIGINT) < 6}}
>  * {{cast(g as timestamp) >= "2020-11-7 00:00:00"}}
>  * {{cast(g as timestamp) BETWEEN "2020-11-01 00:00:00" AND "2020-11-06 
> 00:00:00"}}
> The hint of HIVE-29364 should be taken into account: if the CAST throws away 
> information, the histogram statistics should not be used. E.g., {{{}CAST(128 
> as TINYINT) = -128{}}}, so a {{CAST(intField as TINYINT) > 42}} should not be 
> treated the same as {{{}intField > 42{}}}, if the intField is outside of the 
> range of TINYINT.



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