Little better [#METR-22327].

dbms/src/Storages/MergeTree/MergeTreeData.cpp

@@ -1157,7 +1157,6 @@ MergeTreeData::DataParts MergeTreeData::getDataParts() const
 MergeTreeData::DataPartsVector MergeTreeData::getDataPartsVector() const
 {
 	std::lock_guard<std::mutex> lock(data_parts_mutex);
-
 	return DataPartsVector(std::begin(data_parts), std::end(data_parts));
 }
 

dbms/src/Storages/MergeTree/MergeTreeDataMerger.cpp

@@ -105,7 +105,7 @@ bool MergeTreeDataMerger::selectPartsToMerge(
 {
 	parts.clear();
 
-	MergeTreeData::DataParts data_parts = data.getDataParts();
+	MergeTreeData::DataPartsVector data_parts = data.getDataPartsVector();
 
 	if (data_parts.empty())
 		return false;