多对多表 JOIN

Question

我正在尝试在患者和护士之间建立多对多关系。

我需要将 PatientID 分配给 NurseID；所以病人和护士之间是有关系的。这可以通过函数 TABLE JOIN 实现吗？

到目前为止，我有三个表：

Patient 
(
PatientID (PK), 
Forename, 
surname, 
gender, 
date of birth, 
address, 
illness, 
prioirty
)

seen_by 
(
ID(PK),
PatientID(FK), 
NurseID(FK)
) 

Nurse 
(
NurseID(PK),  
Forename, 
surname
)

我在 seen_by 表中添加了一个外部约束，以添加患者和护士之间的关系。

Patient (PatientID (PK), Forename, surname, gender, date of birth, address, illness, prioirty)

seen_by (ID(PK) PatientID(FK to Patient.PatientID), NurseID(FK to Nurse.NurseID) )

Nurse (NurseID(PK), Forename, surname)

对我做错了什么有什么建议吗？提前谢谢你！

Answer 1

试试这个：

select p.*,s.*,n.* 
from patient as p inner join seen_by as s 
on p.PatientID=s.PatientID
inner join Nurse as n 
on n.NurseID=s.NurseID

如果需要，可以在末尾添加 where

select p.*,s.*,n.* 
from patient as p inner join seen_by as s 
on p.PatientID=s.PatientID
inner join Nurse as n 
on n.NurseID=s.NurseID
where p.field='dumbtext'  -- you can add here the rest of the conditions