Question

我遇到了SQL问题。我有两张桌子：个人和病人治疗。个人表具有个人信息，治疗表具有接受治疗的个人ID和患者ID。我需要找到给不同患者提供最多治疗的个人。我尝试过以下方法：

   SELECT ID , First_Name , Last_Name
   FROM Personal JOIN Patients_Treatments ON ID = Personal_id 
   GROUP BY ID , First_Name , Last_Name
   HAVING COUNT(*) >= ALL (SELECT COUNT(Personal_id) FROM Patients_Treatments 
   GROUP BY Personal_id)

问题在于它给予了给予最多治疗的个人，而不是给予不同患者最多治疗的人。谢谢你的时间！

编辑：如果有兴趣的话，找到解决方案：

SELECT Personal.ID,First_Name,Last_Name
FROM Personal,Patients_Treatments
WHERE Personal.id = Patients_Treatments.Personal_id
GROUP BY Personal.ID,First_Name,Last_Name
HAVING COUNT(distinct Patient_ID) >= all(SELECT COUNT(distinct Patient_ID) 
FROM [Patients_Treatments] GROUP BY Personal_id)

Answer 1

这将返回最高待遇的个人。

SELECT TOP 1 WITH TIES ID , First_Name , Last_Name
FROM Personal JOIN Patients_Treatments ON ID = Personal_id 
GROUP BY ID , First_Name , Last_Name
ORDER BY COUNT(DISTINCT Patient_ID) DESC

在SQL中计算唯一值

1 个答案: