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Posted to issues@spark.apache.org by "Nattavut Sutyanyong (JIRA)" <ji...@apache.org> on 2016/08/08 16:24:20 UTC

[jira] [Created] (SPARK-16951) Alternative implementation of NOT IN to Anti-join

Nattavut Sutyanyong created SPARK-16951:
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             Summary: Alternative implementation of NOT IN to Anti-join
                 Key: SPARK-16951
                 URL: https://issues.apache.org/jira/browse/SPARK-16951
             Project: Spark
          Issue Type: Improvement
          Components: SQL
    Affects Versions: 2.0.0
            Reporter: Nattavut Sutyanyong
             Fix For: 2.1.0


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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