mysql查询某一字段为varchar类型内容是字母和数字，根据数字排序拼接

字母排在前面，数字按小到大排后面

thinkphp代码

$ApplyModel = new ApplyModel();
$where = [];
$goodsList = $ApplyModel
        ->alias('a')
        ->leftJoin("goods g", "a.goodsId = g.id")
        ->where($where)
        ->field("
        a.agreement,
        (a.agreement+0) as agreement2,
        ")
        ->order('agreement2 asc')
        ->select();