diff --git a/src/Storages/MergeTree/MutateTask.cpp b/src/Storages/MergeTree/MutateTask.cpp
index 73b703aa9ca..e958fc49d00 100644
--- a/src/Storages/MergeTree/MutateTask.cpp
+++ b/src/Storages/MergeTree/MutateTask.cpp
@@ -74,7 +74,7 @@ static void splitMutationCommands(
                     mutated_columns.emplace(column_name);
 
                 if (command.type == MutationCommand::Type::MATERIALIZE_COLUMN)
-                     mutated_columns.emplace(command.column_name);
+                    mutated_columns.emplace(command.column_name);
             }
             else if (command.type == MutationCommand::Type::DROP_INDEX || command.type == MutationCommand::Type::DROP_PROJECTION)
             {