有遇到过类似从MySQL数据库中，不需要用特定的类型转化，比如无需操作CAST和CONVERT就能得到查询的结果集全部是字符串的情况吗？

/**
 * 获取系统中该月结算单数据
 *
 * @param $from
 * @param $to
 * @return array|CDbDataReader|mixed
 */
public function getTargetData($from, $to)
{
    $res = $this->targetDb->createCommand("
        SELECT
            platform,
            commission_product_total_amount,
            bill_month,
            refund_total_amount,
            fee_settlement,
            anchor_source,
            fee_adjust_amount,
            commission_product_number,
            refund_sku_number,
            bill_sn,
            buyer_number,
            commission_sku_total_amount,
            fee_total_amount,
            anchor_uid,
            anchor_nickname
        FROM `{$this->targetTable}`
        WHERE bill_month = " . date('Ym', strtotime($from)) . "
    ")->queryAll();
    $this->changeType($res);

    return $res;
}

目前是做一次循环，觉得太过多余

/**
 * 因接口返回值问题，造成数据类型不一致，比如返回的金额为字符或浮点格式，
 * 但是mysql存储为整型等，故将mysql查询后的数据全部转为字符串
 *
 * @param array $list
 */
protected function changeType(&$list = [])
{
    foreach ($list as &$value) {
        foreach ($value as $key => $val) {
            $value[$key] = strval($val);
        }
    }
}