用两次子查询：①第一次子查询剔除最高薪水；②第二次子查询选出剩下人员里薪水最高者即可。
select emp_no, salary, last_name, first_name 
from (select * from employees join salaries using(emp_no)) as tb1
where salary in 
(select max(salary) from salaries where salary not in 
(select max(salary) from salaries)
)