题解 | #截取出年龄#
截取出年龄
https://www.nowcoder.com/practice/b8d8a87fe1fc415c96f355dc62bdd12f
select
substring_index (substring_index (profile, ',', -2), ',', 1) as age,
count(device_id) as number
FROM
user_submit
GROUP BY
age
套娃也是一种很好的办法。
注意不要少打了符号,
