题解 | #统计每种性别的人数#
统计每种性别的人数
https://www.nowcoder.com/practice/f04189f92f8d4f6fa0f383d413af7cb8
select num.gender,count(num.gender) as number from (select device_id, if ( find_in_set ('male', profile) > 0, 'male', 'female' ) as gender from user_submit) as num group by num.gender
通过find函数查找指定字符串,通过返回结果大于0则判断为真,否则为假