题解 | 统计每种性别的人数

select
    gender,
    count(gender) number
from
    (
        select
            right (profile, 4) gender
        from
            user_submit
        where
            profile like '%,male'
    ) a
group by
    a.gender
union all
select
    gender,
    count(gender) number
from
    (
        select
            right (profile, 6) gender
        from
            user_submit
        where
            profile like '%female'
    ) b
group by
    b.gender