个人最后答案: select d.dept_no,d.emp_no,salary as maxSalary from dept_emp as d,salaries as s where d.emp_no = s.emp_no and d.to_date = '9999-01-01' and s.to_date='9999-01-01' and (d.dept_no,salary) in (select d.dept_no,max(s.salary) as maxSalary from dept_emp as d , salaries as s where d.emp_no = s...