我有两个表

db_employee (id,first_name,last_name,salary,department_id) db_dept (department_id,department)

这里是一些示例数据 db_employee id - fist_name - last_name - salary - department_id 10301 - Keith - Morgan - 27056 - 2 10302 - Tyler - Booth - 32199 - 3 db_dept id - department 2 - 人力资源 3 - 运营

我想要输出一个表格，显示员工、他们的薪水以及该员工所在部门的平均薪水。

我尝试先使用子查询找到部门的平均薪水，然后再进行外部查询，但是我遇到了一个错误。

Select first_name, last_name, salary, ( select avg(emp.salary), dep.department from db_employee emp join db_dept dep on emp.department_id=dep.id group by dep.department ) As avgsaldepartment from db_employee