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
    t2.employee_id employee_id,
    t2.department_name department_name,
    performance_score
from
    employee_projects t1 join department_info t2 on t1.employee_id = t2.employee_id
    join(
        select department_name, avg(performance_score) avg_performance_score
        from employee_projects e join department_info d on e.employee_id = d.employee_id
        group by department_name
    ) t3
    on t2.department_name = t3.department_name
where
    performance_score > avg_performance_score
order by
    employee_id