[
https://issues.apache.org/jira/browse/SPARK-40999?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17628245#comment-17628245
]
Apache Spark commented on SPARK-40999:
--------------------------------------
User 'fred-db' has created a pull request for this issue:
https://github.com/apache/spark/pull/38497
> Hints on subqueries are not properly propagated
> -----------------------------------------------
>
> Key: SPARK-40999
> URL: https://issues.apache.org/jira/browse/SPARK-40999
> Project: Spark
> Issue Type: Bug
> Components: Optimizer, Spark Core
> Affects Versions: 3.0.0, 3.0.1, 3.0.2, 3.0.3, 3.1.0, 3.1.1, 3.1.2, 3.2.0,
> 3.1.3, 3.2.1, 3.3.0, 3.2.2, 3.4.0, 3.3.1
> Reporter: Fredrik Klauß
> Priority: Major
>
> Currently, if a user tries to specify a query like the following, the hints
> on the subquery will be lost.
> {code:java}
> SELECT * FROM target t WHERE EXISTS
> (SELECT /*+ BROADCAST */ * FROM source s WHERE s.key = t.key){code}
> This happens as hints are removed from the plan and pulled into joins in the
> beginning of the optimization stage, but subqueries are only turned into
> joins during optimization. As we remove any hints that are not below a join,
> we end up removing hints that are below a subquery.
>
> To resolve this, we add a hint field to SubqueryExpression that any hints
> inside a subquery's plan can be pulled into during EliminateResolvedHint, and
> then pass this hint on when the subquery is turned into a join.
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
