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https://issues.apache.org/jira/browse/SPARK-24607?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16518206#comment-16518206
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Liang-Chi Hsieh commented on SPARK-24607:
-----------------------------------------

Thanks [~mgaido]!

As I check {{Rand}} expression, seems it already uses a seed, it sounds like 
the option 1 in the Hive ticket. So if you still use the same query plan, it 
should produce deterministic sequences of numbers.



> Distribute by rand() can lead to data inconsistency
> ---------------------------------------------------
>
>                 Key: SPARK-24607
>                 URL: https://issues.apache.org/jira/browse/SPARK-24607
>             Project: Spark
>          Issue Type: Bug
>          Components: SQL
>    Affects Versions: 2.2.0, 2.3.1
>            Reporter: zenglinxi
>            Priority: Major
>
> Noticed the following queries can give different results:
> {code:java}
> select count(*) from tbl;
> select count(*) from (select * from tbl distribute by rand()) a;{code}
> this issue was first reported by someone using kylin for building cube with 
> hiveSQL which include  distribute by rand, I think it's also an hidden 
> serious problem in sparksql.



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