[
https://issues.apache.org/jira/browse/HIVE-22074?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16898383#comment-16898383
]
Vineet Garg commented on HIVE-22074:
------------------------------------
The patch adds {{hive.optimize.transform.in.maxnodes}} config which determine
the maximum number of expressions beyond which this transformation will not be
done. Internal experiments have shown 40% improvement in compilation time for
queries containing IN with more than 4000 expressions.
Note that default value 50 is arbitrary.
> Slow compilation due to IN to OR transformation
> -----------------------------------------------
>
> Key: HIVE-22074
> URL: https://issues.apache.org/jira/browse/HIVE-22074
> Project: Hive
> Issue Type: Improvement
> Components: Logical Optimizer
> Reporter: Vineet Garg
> Assignee: Vineet Garg
> Priority: Major
> Attachments: HIVE-22074.1.patch
>
>
> Currently Hive transform IN expressions to OR to apply various CBO rules.
> This incur significant performance hit if IN consist of large number of
> expressions.
> It is better to not transform IN expressions to OR in such cases because
> overall benefit of various optimizations/transformations is unrealized due to
> the compilation overhead
--
This message was sent by Atlassian JIRA
(v7.6.14#76016)
