Question

我有这个查询。我想选择

手术类型
  手术细节
  模态ID

我是否在正确的道路上至少？

LINK表是所有内容的中间

Addmission上的{p> LINK 1toM Surgery上的LINK Mto1 Modality
上的LINK Mto1

我的问题只是在结果中添加Modality.ID 跳过模态，查询工作100％

已更新（删除了多个别名）

SELECT surg.srg_Details, surg.Type, modd.ID
FROM Surgery surg
JOIN LINK lnk on lnk.lnk_ID = surg.srg_lnkID
JOIN Modality modd ON modd.mod_lnkID = lnk.lnk_ID
JOIN Admission adm ON adm.adm_ID = lnk.lnk_admID
WHERE  adm.adm_ID = 192100042

Answer 1

在这种情况下尝试使用：

SELECT surg.srg_Details, surg.Type, mod.ID
FROM Surgery surg, Modality mod
JOIN LINK lnk on lnk.lnk_ID = surg.srg_lnkID
JOIN Admission adm ON adm.adm_ID = lnk.lnk_admID
WHERE  adm.adm_ID = 192100042 AND surg.srg_lnkID = mod.mod_lnkID

Answer 2

Try to use left Join though no match null value will be present

SELECT surg.srg_Details, surg.Type, mod.ID
FROM Surgery surg, Modality mod
left JOIN LINK lnk on lnk.lnk_ID = surg.srg_lnkID
left JOIN Modality mod ON mod.mod_lnkID = lnk.lnk_ID
left JOIN Admission adm ON adm.adm_ID = lnk.lnk_admID
WHERE  adm.adm_ID = 192100042

从具有连接的多表中选择结果

2 个答案: