[
https://issues.apache.org/jira/browse/SPARK-12125?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
iward updated SPARK-12125:
--------------------------
Fix Version/s: 1.6.0
> pull out nondeterministic expressions from Join
> -----------------------------------------------
>
> Key: SPARK-12125
> URL: https://issues.apache.org/jira/browse/SPARK-12125
> Project: Spark
> Issue Type: Bug
> Affects Versions: 1.5.0, 1.5.1, 1.5.2
> Reporter: iward
> Fix For: 1.6.0
>
>
> Currently,*nondeterministic expressions* are only allowed in *Project* or
> *Filter*,And only when we use nondeterministic expressions in *UnaryNode* can
> be pulled out.
> But,Sometime in many case,we will use nondeterministic expressions to process
> *join keys* avoiding data skew.for example:
> {noformat}
> select *
> from tableA a
> join
> (select * from tableB) b
> on upper((case when (a.brand_code is null or a.brand_code = '' ) then cast(
> (-rand() * 10000000 ) as string ) else a.brand_code end )) = b.brand_code
> {noformat}
> This PR introduce a mechanism to pull out nondeterministic expressions from
> *Join*,so we can use nondeterministic expression in *Join* appropriately.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org
For additional commands, e-mail: issues-h...@spark.apache.org
