Github user fhueske commented on a diff in the pull request:
https://github.com/apache/flink/pull/4858#discussion_r146076115
--- Diff:
flink-libraries/flink-table/src/main/scala/org/apache/flink/table/plan/rules/dataSet/DataSetJoinRule.scala
---
@@ -41,8 +41,7 @@ class DataSetJoinRule
val joinInfo = join.analyzeCondition
// joins require an equi-condition or a conjunctive predicate with at
least one equi-condition
- // and disable outer joins with non-equality predicates(see FLINK-5520)
- !joinInfo.pairs().isEmpty && (joinInfo.isEqui || join.getJoinType ==
JoinRelType.INNER)
+ !joinInfo.pairs().isEmpty
--- End diff --
Yes, that is true but the rule are also applied in different contexts.
`FlinkLogicalJoin` is used for the initial translation of batch and stream
programs and `DataSetJoinRule` only for batch. I think it's OK to have these
checks as safety net.
---
