题解 | #平均工资#
平均工资
https://www.nowcoder.com/practice/95078e5e1fba4438b85d9f11240bc591
select AVG(salary) avg_salary from salaries where to_date ='9999-01-01' and salary not in(select MAX(salary ) salary from salaries WHERE to_date ='9999-01-01' union all select min(salary ) salary from salaries WHERE to_date ='9999-01-01')