[
https://issues.apache.org/jira/browse/SPARK-13854?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Liang-Chi Hsieh closed SPARK-13854.
-----------------------------------
Resolution: Not A Problem
> Add constraints to outer join
> -----------------------------
>
> Key: SPARK-13854
> URL: https://issues.apache.org/jira/browse/SPARK-13854
> Project: Spark
> Issue Type: Improvement
> Components: SQL
> Reporter: Liang-Chi Hsieh
>
> Currently, for left outer join we only keep left side constraint. For right
> outer join, we only keep right side constraints. For full outer join, the
> constraints are empty.
> In fact, the constraints are less than the actual constraints for the join
> operator.
> For example, for left outer join, besides the constraints from left side, the
> constraints of right side should be inherited with a bit modification.
> Consider a join as following:
> {code}
> val tr1 = LocalRelation('a.int, 'b.int, 'c.int).subquery('tr1)
> val tr2 = LocalRelation('a.int, 'd.int, 'e.int).subquery('tr2)
> tr1.where('a.attr > 10)
> .join(tr2.where('d.attr < 100), LeftOuter, Some("tr1.a".attr ===
> "tr2.a".attr))
> {code}
> The constraints are not only "a" > 10, "a" is not null. It should also
> include ("d" is null || "d" < 100).
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
