You are viewing a plain text version of this content. The canonical link for it is here.

Posted to issues@spark.apache.org by "Mingcong Han (JIRA)" <ji...@apache.org> on 2019/04/11 10:11:00 UTC

[jira] [Created] (SPARK-27440) Optimize uncorrelated predicate subquery

Mingcong Han created SPARK-27440:
------------------------------------

             Summary: Optimize uncorrelated predicate subquery
                 Key: SPARK-27440
                 URL: https://issues.apache.org/jira/browse/SPARK-27440
             Project: Spark
          Issue Type: Improvement
          Components: SQL
    Affects Versions: 3.0.0
            Reporter: Mingcong Han
             Fix For: 3.0.0


Currently, we rewrite all the predicate subqueries(InSubquery, Exists) as semi-join/anti-join. But uncorrelated predicate subquery can be evaluated using a subplan instead of a join. We can firstly rewrite all the uncorrelated predicate subqueries as `Exists`, then optimize it and compute it using a subquery physical plan like ScalarSubquery. 





--
This message was sent by Atlassian JIRA
(v7.6.3#76005)

---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscribe@spark.apache.org
For additional commands, e-mail: issues-help@spark.apache.org