oracle数据库查询语句

在这个查询语句上，求部门平均工资最高值，显示部门ID等，最后显示一条数据，数据显示部门编号和人数和(部门平均工资）最高值，

SELECT 
    e.department_id,
    COUNT(e.id) AS count,
    MAX(avg_salary) AS max_avg_salary
FROM 
    employees e
JOIN 
    (
        SELECT 
            department_id,
            AVG(salary) AS avg_salary
        FROM 
            employees
        GROUP BY 
            department_id
    ) subquery ON e.department_id = subquery.department_id
GROUP BY 
    e.department_id
ORDER BY 
    max_avg_salary DESC
LIMIT 1;

SELECT MAX(avg_salary) FROM (SELECT AVG(salary) AS avg_salary FROM employee GROUP BY department_id) AS subquery;