with lsb as (select max(s.salary) as ms
from employees e
join salaries s
on e.emp_no = s.emp_no),
lsb2 as (select max(salary) as ms1 from(
select e.emp_no, s.salary, e.last_name, e.first_name
from employees e
join salaries s
on e.emp_no = s.emp_no , lsb
where s.salary < ms) t)
select e.emp_no, s.salary, e.last_name, e.first_name
from employees e
join salaries s
on e.emp_no = s.emp_no, lsb2
where s.salary = ms1

先找到最大的薪资，然后找到小于最大薪资的所有数据，再从这些数据中找打最大的薪资数据，就是第二高的薪资