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https://issues.apache.org/jira/browse/HIVE-18421?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16356202#comment-16356202
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Vihang Karajgaonkar commented on HIVE-18421:
--------------------------------------------

Okay, I finally figured out the problem with vectorization_numeric_overflows.q. 
Turns out on CentOS the ordering of rows is different for a query result when 
compared to Ubuntu/MacOS. Both the results are valid since the key on which the 
order by clause was issued have same value on 2 rows. So the order of these 2 
rows with the same value of key is non-deterministic. Fixed the query so that 
it orders by a different column which is always deterministic.

> Vectorized execution handles overflows in a different manner than 
> non-vectorized execution
> ------------------------------------------------------------------------------------------
>
>                 Key: HIVE-18421
>                 URL: https://issues.apache.org/jira/browse/HIVE-18421
>             Project: Hive
>          Issue Type: Bug
>          Components: Vectorization
>    Affects Versions: 2.1.1, 2.2.0, 3.0.0, 2.3.2
>            Reporter: Vihang Karajgaonkar
>            Assignee: Vihang Karajgaonkar
>            Priority: Major
>         Attachments: HIVE-18421.01.patch, HIVE-18421.02.patch, 
> HIVE-18421.03.patch, HIVE-18421.04.patch, HIVE-18421.05.patch, 
> HIVE-18421.06.patch, HIVE-18421.07.patch
>
>
> In vectorized execution arithmetic operations which cause integer overflows 
> can give wrong results. Issue is reproducible in both Orc and parquet.
> Simple test case to reproduce this issue
> {noformat}
> set hive.vectorized.execution.enabled=true;
> create table parquettable (t1 tinyint, t2 tinyint) stored as parquet;
> insert into parquettable values (-104, 25), (-112, 24), (54, 9);
> select t1, t2, (t1-t2) as diff from parquettable where (t1-t2) < 50 order by 
> diff desc;
> +-------+-----+-------+
> |  t1   | t2  | diff  |
> +-------+-----+-------+
> | -104  | 25  | 127   |
> | -112  | 24  | 120   |
> | 54    | 9   | 45    |
> +-------+-----+-------+
> {noformat}
> When vectorization is turned off the same query produces only one row.



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