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https://issues.apache.org/jira/browse/SPARK-38832?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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XiDuo You updated SPARK-38832:
------------------------------
    Description: 
We can remove the distinct in aggregate expression if the child distinct 
semantics is guaranteed.

For example:
{code:java}
SELECT count(distinct c) FROM (
  SELECT c FROM t GROUP BY c
){code}
 

 

 

  was:
We can remove the distinct in aggregate expression if the child distinct 
semantics is guaranteed.

For example:

 
{code:java}
SELECT count(distinct c) FROM (
  SELECT c FROM t GROUP BY c
){code}
 

 

 


> Remove unnecessary distinct in aggregate expression by distinctKeys
> -------------------------------------------------------------------
>
>                 Key: SPARK-38832
>                 URL: https://issues.apache.org/jira/browse/SPARK-38832
>             Project: Spark
>          Issue Type: Improvement
>          Components: SQL
>    Affects Versions: 3.4.0
>            Reporter: XiDuo You
>            Priority: Major
>
> We can remove the distinct in aggregate expression if the child distinct 
> semantics is guaranteed.
> For example:
> {code:java}
> SELECT count(distinct c) FROM (
>   SELECT c FROM t GROUP BY c
> ){code}
>  
>  
>  



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