题解 | 当前各个title类型对应的员工当前薪水的平均工资
统计出当前各个title类型对应的员工当前薪水对应的平均工资
https://www.nowcoder.com/practice/c8652e9e5a354b879e2a244200f1eaae
select title,avg(salary) from ( select b.emp_no,b.salary,a.title from titles a left join salaries b on a.emp_no = b.emp_no )h group by title order by avg(salary)