题解 | #顾客登录名#
顾客登录名
https://www.nowcoder.com/practice/7cbf5e3082954c21a80fc750ce97350f
select cust_id, cust_name, upper(concat(substring(cust_contact, 1, 2), substring(cust_city, 1, 3))) user_login from Customers # 大写字母转换函数upper # 拼接函数concat # 获取每列前几个字符substring(columnname, 第几个字符开始, 获取前几个字符)