diff --git a/src/Functions/FunctionsExternalDictionaries.h b/src/Functions/FunctionsExternalDictionaries.h
index 5f94a1e1f4b..14a6430723c 100644
--- a/src/Functions/FunctionsExternalDictionaries.h
+++ b/src/Functions/FunctionsExternalDictionaries.h
@@ -293,7 +293,6 @@ public:
     size_t getNumberOfArguments() const override { return 0; }
 
     bool useDefaultImplementationForConstants() const final { return true; }
-    bool useDefaultImplementationForNulls() const final { return false; }
     ColumnNumbers getArgumentsThatAreAlwaysConstant() const final { return {0, 1}; }
 
     bool isDeterministic() const override { return false; }