自用题解
查找所有员工自入职以来的薪水涨幅情况
http://www.nowcoder.com/questionTerminal/fc7344ece7294b9e98401826b94c6ea5
select DISTINCT e.emp_no,(s2.salary-s1.salary) as growth from employees as e -- 找到入职的薪资表 join salaries as s1 on e.emp_no=s1.emp_no and s1.from_date=e.hire_date -- 找到当前的薪资表 join salaries as s2 on e.emp_no=s2.emp_no and s2.to_date='9999-01-01' order by growth asc