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https://issues.apache.org/jira/browse/HIVE-26312?focusedWorklogId=822496&page=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-822496
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ASF GitHub Bot logged work on HIVE-26312:
-----------------------------------------

                Author: ASF GitHub Bot
            Created on: 02/Nov/22 00:26
            Start Date: 02/Nov/22 00:26
    Worklog Time Spent: 10m 
      Work Description: github-actions[bot] closed pull request #3359: 
HIVE-26312: Use default digest normalization strategy in CBO
URL: https://github.com/apache/hive/pull/3359




Issue Time Tracking
-------------------

    Worklog Id:     (was: 822496)
    Time Spent: 1h  (was: 50m)

> Use default digest normalization strategy in CBO
> ------------------------------------------------
>
>                 Key: HIVE-26312
>                 URL: https://issues.apache.org/jira/browse/HIVE-26312
>             Project: Hive
>          Issue Type: Task
>          Components: CBO
>    Affects Versions: 4.0.0-alpha-1
>            Reporter: Stamatis Zampetakis
>            Assignee: Stamatis Zampetakis
>            Priority: Major
>              Labels: pull-request-available
>          Time Spent: 1h
>  Remaining Estimate: 0h
>
> CALCITE-2450 introduced a way to improve planning time by normalizing some 
> query expressions (RexNodes). The behavior can be enabled/disabled via the 
> following system property: calcite.enable.rexnode.digest.normalize
> There was an attempt to disable the normalization explicitly in HIVE-23456 to 
> avoid rendering HiveFilterSortPredicates rule useless. However, the [way the 
> normalization is disabled 
> now|https://github.com/apache/hive/blob/f29cb2245c97102975ea0dd73783049eaa0947a0/ql/src/java/org/apache/hadoop/hive/ql/metadata/Hive.java#L549],
>  dependents on the way classes are loaded. If for some reason 
> CalciteSystemProperty is loaded before hitting the respective line in 
> Hive.java setting the property will not have any effect.
> After HIVE-26238 the behavior of the rule is not dependent in the value of 
> the property so there is nothing holding us back from enabling the 
> normalization.
> At the moment there is not strong reason to enable or disable the 
> normalization explicitly so it is better to rely on the default value 
> provided by Calcite to avoid running with different normalization strategy 
> when the class loading order changes.



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