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https://issues.apache.org/jira/browse/HIVE-14002?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15330819#comment-15330819
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Ashutosh Chauhan commented on HIVE-14002:
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I am not sure if we can allow *any* operators between two RSs other than GBy.
e.g., filter can be problematic if first Limit only generates N rows which
filters eat all of it. We will get incorrect result. Even for Select operator
we can allow this only for column references and constants.
> Extend limit propagation to subsequent RS operators
> ---------------------------------------------------
>
> Key: HIVE-14002
> URL: https://issues.apache.org/jira/browse/HIVE-14002
> Project: Hive
> Issue Type: Improvement
> Components: Physical Optimizer
> Affects Versions: 2.2.0
> Reporter: Nita Dembla
> Assignee: Jesus Camacho Rodriguez
> Attachments: HIVE-14002.patch
>
>
> In some occasions, for instance when RS dedup does not kick in, it is useful
> to propagate the limit to subsequent RS operators, as this will reduce
> intermediary results and impact performance. This issue covers that extension.
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