题解 | #平均工资#
平均工资
http://www.nowcoder.com/practice/95078e5e1fba4438b85d9f11240bc591
select avg(salary) from salaries where salary not in ( select min(salary) from salaries where to_date = '9999-01-01' union select max(salary) from salaries where to_date = '9999-01-01' ) and to_date = '9999-01-01'