with t1 as(
select distinct

    department_name,
    avg(performance_score) over (
        partition by
            department_name
    ) as avg_performance_score
from
    employee_projects
    left join department_info using (employee_id)
)
select employee_id,department_name,performance_score
from employee_projects
left join department_info using(employee_id)
left join t1 using(department_name)
where performance_score > avg_performance_score