题解 | #查找在职员工自入职以来的薪水涨幅情况#

select
    s1.emp_no,
    (s2.salary - s1.salary) as growth
from
    salaries as s1
    join salaries as s2 on s1.emp_no = s2.emp_no
    and s2.to_date = '9999-01-01'
    and (s1.emp_no, s1.from_date) in (
        select
            emp_no,
            min(from_date)
        from
            salaries
        group by
            emp_no
    )
order by
    growth;