diff --git a/cpp-ch/local-engine/Storages/CustomStorageMergeTree.cpp b/cpp-ch/local-engine/Storages/CustomStorageMergeTree.cpp
index e498dc0c325d6..c767a6fd3e7aa 100644
--- a/cpp-ch/local-engine/Storages/CustomStorageMergeTree.cpp
+++ b/cpp-ch/local-engine/Storages/CustomStorageMergeTree.cpp
@@ -92,5 +92,8 @@ std::unique_ptr<MergeTreeSettings> CustomStorageMergeTree::getDefaultSettings()
 {
     throw std::runtime_error("not implement");
 }
-
+std::map<std::string, MutationCommands> CustomStorageMergeTree::getUnfinishedMutationCommands() const
+{
+    throw std::runtime_error("not implement");
+}
 }
diff --git a/cpp-ch/local-engine/Storages/CustomStorageMergeTree.h b/cpp-ch/local-engine/Storages/CustomStorageMergeTree.h
index e61a54eef142b..4ac989d21206c 100644
--- a/cpp-ch/local-engine/Storages/CustomStorageMergeTree.h
+++ b/cpp-ch/local-engine/Storages/CustomStorageMergeTree.h
@@ -45,6 +45,7 @@ class CustomStorageMergeTree final : public MergeTreeData
     std::string getName() const override;
     std::vector<MergeTreeMutationStatus> getMutationsStatus() const override;
     bool scheduleDataProcessingJob(BackgroundJobsAssignee & executor) override;
+    std::map<std::string, MutationCommands> getUnfinishedMutationCommands() const override;
 
     MergeTreeDataWriter writer;
     MergeTreeDataSelectExecutor reader;
@@ -64,7 +65,6 @@ class CustomStorageMergeTree final : public MergeTreeData
     void replacePartitionFrom(const StoragePtr & source_table, const ASTPtr & partition, bool replace, ContextPtr context) override;
     void movePartitionToTable(const StoragePtr & dest_table, const ASTPtr & partition, ContextPtr context) override;
     bool partIsAssignedToBackgroundOperation(const DataPartPtr & part) const override;
-    size_t getNumberOfUnfinishedMutations() const override { return 0; }
     std::map<int64_t, MutationCommands> getAlterMutationCommandsForPart(const DataPartPtr & /*part*/) const override { return {}; }
     void attachRestoredParts(MutableDataPartsVector && /*parts*/) override { throw std::runtime_error("not implement"); }
 };