diff --git a/dbms/src/Storages/MergeTree/MergeTreeDataMergerMutator.cpp b/dbms/src/Storages/MergeTree/MergeTreeDataMergerMutator.cpp
index 7c4b3fd1fcb..1d064b9b0c7 100644
--- a/dbms/src/Storages/MergeTree/MergeTreeDataMergerMutator.cpp
+++ b/dbms/src/Storages/MergeTree/MergeTreeDataMergerMutator.cpp
@@ -1032,7 +1032,7 @@ MergeTreeData::MutableDataPartPtr MergeTreeDataMergerMutator::mutatePartToTempor
         NameSet files_to_skip = {"checksums.txt", "columns.txt"};
 
         auto mrk_extension = data_settings->index_granularity_bytes ? getAdaptiveMrkExtension() : getNonAdaptiveMrkExtension();
-        for (const auto & entry : in_header)
+        for (const auto & entry : updated_header)
         {
             IDataType::StreamCallback callback = [&](const IDataType::SubstreamPath & substream_path)
             {