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
    e.employee_id as employee_id,
    department_name,
    performance_score
from
    employee_projects as e
    inner join department_info as d on e.employee_id = d.employee_id
    inner join (
        select
            department_id,
            avg(performance_score) as avg_score
        from
            employee_projects as e
            inner join department_info as d on e.employee_id = d.employee_id
        group by
            department_id
    ) as a on d.department_id = a.department_id
where
    performance_score > avg_score
order by
    employee_id;