code: function _groupsOrders(type) {
      var items = this.grouped[type];
      if (!items) {
        return '';
      }
      var formatter = this.formatter;
      var sql = items.map(function (item) {
        return (item.value instanceof Raw ? formatter.unwrapRaw(item.value) : formatter.columnize(item.value)) + (type === 'order' && item.type !== 'orderByRaw' ? ' ' + formatter.direction(item.direction) : '');
      });
      return sql.length ? type + ' by ' + sql.join(', ') : '';
    }
docs: Compiles the `order by` statements.