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https://issues.apache.org/jira/browse/PIG-4819?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Koji Noguchi reopened PIG-4819:
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Sorry for reopening but my unit test {{testRANDOMWithJob}} was failing
indicating that random isn't random enough.
Trying with a real cluster with small inputs, saw a very similar random values
produced with high probability. Obviously long "seed" was too close. Changing
how I'm setting the seed.
> RANDOM() udf can lead to missing or redundant records
> -----------------------------------------------------
>
> Key: PIG-4819
> URL: https://issues.apache.org/jira/browse/PIG-4819
> Project: Pig
> Issue Type: Bug
> Reporter: Koji Noguchi
> Assignee: Koji Noguchi
> Fix For: 0.16.0
>
> Attachments: pig-4819-v01.patch, pig-4819-v02.patch
>
>
> When RANDOM() value is used for grouping/distinct/etc, it breaks the
> mapreduce rule and can lead to redundant or missing records.
> Some discussion can be found in
> https://issues.apache.org/jira/browse/PIG-3257?focusedCommentId=13669195#comment-13669195
> We should make RANDOM less random so that it'll produce the same sequence of
> random values from the task retries.
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