Github user maropu commented on a diff in the pull request:
https://github.com/apache/spark/pull/19364#discussion_r141772352
--- Diff:
sql/core/src/main/scala/org/apache/spark/sql/execution/exchange/ExchangeCoordinator.scala
---
@@ -232,7 +232,7 @@ class ExchangeCoordinator(
Github user maropu commented on a diff in the pull request:
https://github.com/apache/spark/pull/19364#discussion_r141772266
--- Diff:
sql/core/src/main/scala/org/apache/spark/sql/execution/exchange/ExchangeCoordinator.scala
---
@@ -232,7 +232,7 @@ class ExchangeCoordinator(
GitHub user liutang123 opened a pull request:
https://github.com/apache/spark/pull/19364
[SPARK-22144] ExchangeCoordinator combine the partitions of an 0 sized
pre-shuffle to 0
## What changes were proposed in this pull request?
when the length of pre-shuffle's partitions is 0,
