题解 | 分析员工在不同项目中的绩效表现以及所属部门的平均绩效情况

select employee_id
,department_name
,performance_score
from (
    select employee_id
    ,department_name
    ,performance_score
    ,avg(performance_score)over(partition by department_name) as avg_ps
    from employee_projects join department_info using(employee_id)
    group by department_name,employee_id
) as t
where performance_score > avg_ps
order by employee_id ASC;