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apache · Aug 19, 2019 · 398a891 · 398a891
1 parent 1256c87
commit 398a891
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/sql/core/src/main/scala/org/apache/spark/sql/execution/exchange/ShuffleExchangeExec.scala b/sql/core/src/main/scala/org/apache/spark/sql/execution/exchange/ShuffleExchangeExec.scala
@@ -264,6 +264,10 @@ object ShuffleExchangeExec {
             prefixComparator,
             prefixComputer,
             pageSize,
+            // As we need to compare the binary of UnsafeRow here, we can't make sure whether all
+            // the fields can sort fully with prefix like SortExec. So we disable radix sort here
+            // to avoid getting unstable sort, and result to a correctness bug.
+            // See more details in SPARK-28699.
             false /* canUseRadixSort */)
           sorter.sort(iter.asInstanceOf[Iterator[UnsafeRow]])
         }