text: #pragma once
  #include <Processors/ISource.h>
  
  
  namespace DB
  {
  
  class NullSource : public ISource
  {
  public:
      explicit NullSource(Block header) : ISource(std::move(header)) {}
      String getName() const override { return "NullSource"; }
  
  protected:
      Chunk generate() override { return Chunk(); }
  };
  
  }
  