configure_on_duplicate_update_logic

# File activerecord/lib/active_record/insert_all.rb, line 125
      def configure_on_duplicate_update_logic
        if custom_update_sql_provided? && update_only.present?
          raise ArgumentError, "You can't set :update_only and provide custom update SQL via :on_duplicate at the same time"
        end

        if update_only.present?
          @updatable_columns = Array(update_only)
          @on_duplicate = :update
        elsif custom_update_sql_provided?
          @update_sql = on_duplicate
          @on_duplicate = :update
        elsif @on_duplicate == :update && updatable_columns.empty?
          @on_duplicate = :skip
        end
      end