[GitHub] [spark] cloud-fan commented on a change in pull request #28954: [SPARK-32083][SQL] Apply CoalesceShufflePartitions when input RDD has 0 partitions with AQE

[GitBox <gi...@apache.org>]

cloud-fan commented on a change in pull request #28954:
URL: https://github.com/apache/spark/pull/28954#discussion_r447746879



##########
File path: sql/core/src/main/scala/org/apache/spark/sql/execution/adaptive/CoalesceShufflePartitions.scala
##########
@@ -79,8 +66,29 @@ case class CoalesceShufflePartitions(session: SparkSession) extends Rule[SparkPl
           case stage: ShuffleQueryStageExec if stageIds.contains(stage.id) =>
             CustomShuffleReaderExec(stage, partitionSpecs)
         }
+      }
+
+      if (validMetrics.isEmpty) {

Review comment:
       if a query stage has multiple leaf shuffles, and only one of them has 0-partition input RDD. What shall we do?




----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

For queries about this service, please contact Infrastructure at:
users@infra.apache.org



---------------------------------------------------------------------
To unsubscribe, e-mail: reviews-unsubscribe@spark.apache.org
For additional commands, e-mail: reviews-help@spark.apache.org