给出employees表中排名为奇数行的first_name
给出employees表中排名为奇数行的first_name
https://www.nowcoder.com/practice/e3cf1171f6cc426bac85fd4ffa786594
with t1 as (
select e2.first_name,
count(*) as rownum
from employees as e2
left join employees as e1
on e1.first_name <= e2.first_name
group by e2.first_name
) select first_name from t1 where rownum % 2 = 1;
