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(
SUBSTR((cust_contact),1,2),//注意substr是从1开始，substrb是从0开始，列名时要用括号
SUBSTR((cust_city),1,3)
)
) AS user_login
FROM Customers;
