题解 | #查找在职员工自入职以来的薪水涨幅情况#

# #最开始工资
# select employees.emp_no e1,salary s1,from_date f1,to_date t2
# from employees left join salaries on (employees.emp_no=salaries.emp_no)
# where hire_date = from_date

# #最新的工资
# select salaries.emp_no e2,salary s2,from_date f2,to_date t2
# from salaries
# where to_date = '9999-01-01'


select e1,s2-s1 growth
from (select employees.emp_no e1,salary s1,from_date f1,to_date t2
from employees left join salaries on (employees.emp_no=salaries.emp_no)
where hire_date = from_date)t1 right join (select salaries.emp_no e2,salary s2,from_date f2,to_date t2
from salaries
where to_date = '9999-01-01')t3 on (e1=e2)
order by growth