我觉得这个有点缺陷to_date=不一定是9999-01-01,如果to_date一定是9999-01-01，那这题就不配困难好吧。万一有人离职了，但是依旧要算涨薪多少呢？可以帮我看看这个 select c2.emp_no, (c2.salary-c1.salary) growth from (select s1.emp_no, s1.salary from employees e1 join salaries s1 on e1.emp_no=s1.emp_no and e1.hire_date=s1.from_date) c1 join (select s2.emp_no, s2.salary,rank()over(partition by s2.emp_no order by to_date desc) as t from employees e2 join salaries s2 on e2.emp_no=s2.emp_no) c2 on c1.emp_no=c2.emp_no where t=1