题解 | #截取出年龄#
截取出年龄
http://www.nowcoder.com/practice/b8d8a87fe1fc415c96f355dc62bdd12f
select
#sql中subString_index的嵌套使用的用法
SUBSTRING_INDEX(SUBSTRING_INDEX(profile,',',3),',',-1) as age,
count(device_id) as NUMBER
from user_submit
group by age;
