题解 | #平均工资#
平均工资
http://www.nowcoder.com/practice/95078e5e1fba4438b85d9f11240bc591
SELECT AVG(salary) FROM salaries WHERE to_date = '9999-01-01' AND salary <> (SELECT MAX(salary) FROM salaries WHERE to_date = '9999-01-01') AND salary <> (SELECT MIN(salary) FROM salaries WHERE to_date = '9999-01-01');