题解 | #查找在职员工自入职以来的薪水涨幅情况#

select new.emp_no, new_salary-old_salary growth from (
select emp_no, min(salary) old_salary from salaries s group by emp_no) old inner join (
select emp_no, max(salary) new_salary from salaries s where to_date="9999-01-01" group by emp_no) new
on old.emp_no=new.emp_no order by growth

不需要用到第一个表，因为员工入职之后不会降薪，所以只根据salaries表找出员工的最大工资（要求当前员工所以to_date ="9999-01-01"）和最小工资进行相减就可以了