code: def save_associations
        self.class.associations.each do |association_data|
          association_name = association_data[:name]
  
          next unless send("#{association_name}_used?") && association = send(association_name)
  
          inline_creation = association_data[:inline] == :create && new_record?
          changed = association.is_a?(Collection) || association.changed?
  
          if association.respond_to?(:save) && changed && !inline_creation && association.save
            send("#{association_name}=", association) # set id/ids columns
          end
  
          if (association_data[:inline] == true || inline_creation) && changed
            attributes[association_name] = association.to_param
          end
        end
      end
docs: Saves associations
   Takes into account inlining, collections, and id setting on the parent resource.