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https://issues.apache.org/jira/browse/IMPALA-7814?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Tim Armstrong updated IMPALA-7814:
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    Component/s: Frontend

> AggregationNode's memory estimate should be based on NDV only for 
> non-grouping aggs 
> ------------------------------------------------------------------------------------
>
>                 Key: IMPALA-7814
>                 URL: https://issues.apache.org/jira/browse/IMPALA-7814
>             Project: IMPALA
>          Issue Type: Sub-task
>          Components: Frontend
>            Reporter: Pooja Nilangekar
>            Assignee: Pooja Nilangekar
>            Priority: Major
>              Labels: resource-management
>
> Currently, the AggregationNode always computes the NDV to estimate the number 
> of rows. However, for grouping aggregates, the entire input has to be 
> consumed before the output can be produced, hence its memory estimate should 
> not consider the NDV.  This is acceptable for non-grouping aggregates because 
> it only need to store the value expression during the build phase, instead of 
> the entire tuple. 



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