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https://issues.apache.org/jira/browse/SPARK-16951?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Herman van Hovell updated SPARK-16951:
--------------------------------------
    Issue Type: Sub-task  (was: Improvement)
        Parent: SPARK-18455

> Alternative implementation of NOT IN to Anti-join
> -------------------------------------------------
>
>                 Key: SPARK-16951
>                 URL: https://issues.apache.org/jira/browse/SPARK-16951
>             Project: Spark
>          Issue Type: Sub-task
>          Components: SQL
>    Affects Versions: 2.0.0
>            Reporter: Nattavut Sutyanyong
>
> A transformation currently used to process {{NOT IN}} subquery is to rewrite 
> to a form of Anti-join with null-aware property in the Logical Plan and then 
> translate to a form of {{OR}} predicate joining the parent side and the 
> subquery side of the {{NOT IN}}. As a result, the presence of {{OR}} 
> predicate is limited to the nested-loop join execution plan, which will have 
> a major performance implication if both sides' results are large.
> This JIRA sketches an idea of changing the OR predicate to a form similar to 
> the technique used in the implementation of the Existence join that addresses 
> the problem of {{EXISTS (..) OR ..}} type of queries.



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