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From "Jinfeng Ni" <...@maprtech.com>
Subject Re: Review Request 32248: DRILL-2139: Star is not expanded correctly in "select distinct" query
Date Thu, 19 Mar 2015 18:35:48 GMT

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This is an automatically generated e-mail. To reply, visit:
https://reviews.apache.org/r/32248/#review77076
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A couple of comments after a quick look at the code. 

Will look more in detail later.


exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/aggregate/HashAggBatch.java
<https://reviews.apache.org/r/32248/#comment124916>

    Can you show example where you will expect to see "*" in the aggregate expression? For
distinct * over schemaless table, I assume the * will appear in the GroupBy keys, not in the
aggregated expressions. For count(*) as the agg expression, planner will replace * with a
constant. So, I could not see why it is necessary to check if there is star in the aggregated
expression.



exec/java-exec/src/test/java/org/apache/drill/TestExampleQueries.java
<https://reviews.apache.org/r/32248/#comment124917>

    Have you consider the case where * comes from join?
    
    select distinct * from dept, emp where ...
    
    Seems the code you added will not work properly for such case.


- Jinfeng Ni


On March 19, 2015, 11:31 a.m., Sean Hsuan-Yi Chu wrote:
> 
> -----------------------------------------------------------
> This is an automatically generated e-mail. To reply, visit:
> https://reviews.apache.org/r/32248/
> -----------------------------------------------------------
> 
> (Updated March 19, 2015, 11:31 a.m.)
> 
> 
> Review request for drill, Aman Sinha and Jinfeng Ni.
> 
> 
> Bugs: DRILL-2139
>     https://issues.apache.org/jira/browse/DRILL-2139
> 
> 
> Repository: drill-git
> 
> 
> Description
> -------
> 
> Expand * at the run time
> 
> 
> Diffs
> -----
> 
>   exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/aggregate/HashAggBatch.java
c29fbf2 
>   exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/aggregate/StreamingAggBatch.java
33d2c7a 
>   exec/java-exec/src/main/java/org/apache/drill/exec/physical/impl/xsort/ExternalSortBatch.java
a23780e 
>   exec/java-exec/src/test/java/org/apache/drill/TestExampleQueries.java d2d97f8 
>   exec/java-exec/src/test/java/org/apache/drill/exec/physical/impl/agg/TestHashAggr.java
3786bfd 
>   exec/java-exec/src/test/resources/store/text/data/repeatedRows.json PRE-CREATION 
> 
> Diff: https://reviews.apache.org/r/32248/diff/
> 
> 
> Testing
> -------
> 
> Unit and all QA tests passed.
> 
> 
> Thanks,
> 
> Sean Hsuan-Yi Chu
> 
>


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