[GitHub] [spark] HyukjinKwon commented on a diff in pull request #37855: [WIP][SPARK-40407][SQL] Fix the potential data skew caused by df.repartition

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

HyukjinKwon commented on code in PR #37855:
URL: https://github.com/apache/spark/pull/37855#discussion_r969204188


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sql/core/src/main/scala/org/apache/spark/sql/execution/exchange/ShuffleExchangeExec.scala:
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@@ -298,8 +297,7 @@ object ShuffleExchangeExec {
     }
     def getPartitionKeyExtractor(): InternalRow => Any = newPartitioning match {
       case RoundRobinPartitioning(numPartitions) =>
-        // Distributes elements evenly across output partitions, starting from a random partition.

Review Comment:
   I think removing this can actually cause a regression such as skewed data since the starting partition is always same?



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