sql - 集体最大值

Question

我有一个这样的表结构:

employee
    id int
    manager_id int (the employee id of the manager)
    name
    ...

awards
    id int
    employee_id int
    points int (the award "value")

我如何找到其员工(直接向经理汇报的人员)总共获得最多奖励积分的经理？

Answer 1

像这样:

SELECT
    mgr.id,
    mgr.name,
    SUM(awd.points) As TotalStaffPoints
FROM    employee As mgr
JOIN    employee As stf ON mgr.id = stf.manager_id
JOIN    awards   As awd ON stf.id = awd.employee_id
GROUP BY mgr.id, mgr.name
ORDER BY TotalStaffPoints DESC