diff --git a/dbms/src/DataStreams/NullAndDoCopyBlockInputStream.h b/dbms/src/DataStreams/NullAndDoCopyBlockInputStream.h
index 961f2b77bca..296f198b01a 100644
--- a/dbms/src/DataStreams/NullAndDoCopyBlockInputStream.h
+++ b/dbms/src/DataStreams/NullAndDoCopyBlockInputStream.h
@@ -32,7 +32,7 @@ public:
 
     String getName() const override { return "NullAndDoCopy"; }
 
-    Block getHeader() const override { return input->getHeader(); }
+    Block getHeader() const override { return {}; }
 
 protected:
     Block readImpl() override