diff --git a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/UnsupportedOperationChecker.scala b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/UnsupportedOperationChecker.scala
index a5eded631fd9b46a9b3836805bcd62dcce25f237..f0b68abfdc1b4d77ad1d7c6ab41ef46b3456978a 100644
--- a/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/UnsupportedOperationChecker.scala
+++ b/sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/UnsupportedOperationChecker.scala
@@ -166,7 +166,7 @@ object UnsupportedOperationChecker {
           throwError("Limits are not supported on streaming DataFrames/Datasets")
 
         case Sort(_, _, _) if !containsCompleteData(subPlan) =>
-          throwError("Sorting is not supported on streaming DataFrames/Datasets, unless it is on" +
+          throwError("Sorting is not supported on streaming DataFrames/Datasets, unless it is on " +
             "aggregated DataFrame/Dataset in Complete output mode")
 
         case Sample(_, _, _, _, child) if child.isStreaming =>