题解 | #查找employees表emp_no与last_name的员工信息#
截取出年龄
http://www.nowcoder.com/practice/b8d8a87fe1fc415c96f355dc62bdd12f
截取关键信息年龄使用函数
SUBSTRING(string, position, length)
解题:
SELECT SUBSTRING(profile,12,2) as age, COUNT(*)
from user_submit
GROUP by age
from user_submit
GROUP by age