用重复的列名在SQL中联接三个表

Question

我在SQL中有三个表，需要将它们连接在一起，这是一个简化的版本：

表1列

Person ID (pID)
Fav Soccer Team (favST)
Fav Soccer Player (favSP)

表2列

Person ID (pID) 
Fav Soccer Team (favST) 
Fav Soccer Player (favSP)

表3列

Person ID (person_ID)
Person Name (pName)

问题在于每个人都可能同时出现在表1和表2中。您可以举个例子，表1反映了2017年最喜欢的球队和球员，表2反映了2018年最喜欢的球队和球员。

我必须创建一个查询，将所有查询都加入并显示

结果列

Person ID (pID) 
Person Name (pName)
Favourite Soccer Team (favST) 
Favourite Soccer Player (favSP)
Table1/Table2 <--- which table this row of data is from

Answer 1

尝试以下操作：

Select
  Table3.person_ID,
  Table3.pName,
  X.favST,
  X.favSP,
  X.tname
From
  Table3
Left join
  (
  Select
    PID,
    FavST,
    FavSP,
    'Table1' as tname
   From
    Table1
  Union
  Select
    PID,
    FavST,
    FavSP,
    'Table2' as tname
   From
    Table2
  )X on x.pId = table3.person_ID;