题解 | #平均工资#

方法一
select (sum(salary)-min(salary)-max(salary))/(count(salary)-2) avgsalary
from salaries
where to_date = "9999-01-01"
方法二
select avg(salary)
from salaries
where salary not in (
    select max(salary)
    from salaries
    where to_date like '9999-01-01') and salary not in (
    select min(salary)
    from salaries
    where to_date like '9999-01-01') and to_date = "9999-01-01"