alter_table(:classification_creator_rlshp) do
      add_foreign_key([:agent_person_id], :agent_person, :key => :id)
      add_foreign_key([:agent_family_id], :agent_family, :key => :id)
      add_foreign_key([:agent_corporate_entity_id], :agent_corporate_entity, :key => :id)
      add_foreign_key([:agent_software_id], :agent_software, :key => :id)