思路

1.先把入职时间分组，然后按入职时间排序，取倒数第三名时间。

select hire_date from employees
group by hire_date
order by hire_date desc
limit 2,1; js

2.然后按上面的日期匹配员工即可

select * from employees 
where hire_date=(
    select hire_date from employees
    group by hire_date
    order by hire_date desc
    limit 2,1
);