#解题步骤：
#1.找出入职薪资
#2.找出当前薪资
#3.把前两步进行联结，将两次薪水相减即可
#薪资涨幅=当前薪资-入职薪资
select a.emp_no,(t.salary-b.salary)as growth
from employees as a 
inner join salaries as b
on a.hire_date=b.from_date 
inner join salaries as t
on a.emp_no=t.emp_no and t.to_date='9999-01-01'
order by growth