根据一个表中的唯一 ID 连接多个表

Question

我想根据从第一个表中获取的 ID 加入多个表。

这是一个例子：

地点：

ID	位置 ID
1	25
2	15
3	33

序列化表：

位置 ID	产品ID	序列号
25	4545454	ABC123
25	1231233	CBA321
25	5432121	BCA213

非序列化表：

位置 ID	产品ID	数量
25	6786788	3
25	9898989	15
25	8786678	24

我正在尝试返回一个看起来像这个结果表的表

ID	Location_ID	产品_ID	序列号	数量
1	25	4545454	ABC123	NULL
1	25	1231233	CBA321	NULL
1	25	5432121	BCA213	NULL
1	25	6786788	NULL	3
1	25	9898989	NULL	15
1	25	8786678	NULL	24

SELECT
    Location.ID AS ID,
    Location.LocationID AS Location_ID,
    *** NOT SURE how to fetch ProductID From Both Tables *** Product_ID, 
    Serialized.SerialNumber AS Serial_Num,      
    NonSerialized.Quantity AS Quantity,
    FROM Location
    INNER JOIN NonSerialized ON Location.LocationID = NonSerialized.LocationID
    INNER JOIN Serialized ON Location.LocationID = Serialized.LocationID
    WHERE Location.ID = 1 

Answer 1

select loc.Id, loc.locationId, s.ProductId, s.SerialNumber, null as Quantity   
from Location loc
inner join Serialized s on loc.LocationId = s.locationId
where loc.Id = 1
union
select loc.Id, loc.locationId, ns.ProductId, null, ns.Quantity   
from Location loc
inner join nonSerialized ns on loc.LocationId = ns.locationId
where loc.Id = 1

会做的。 您需要合并 2 组数据中的数据。

Answer 2

你需要做一个联合，从两个表中获取行：

select loc.ID, loc.LocationID, s.ProductID, s.SerialNumber, 
       null as Quantity
  from Location loc
  join Serialized s on s.ID = loc.ID
union all
select loc.ID, loc.LocationID, ns.ProductID, null as SerialNumber, 
       ns.Quantity
  from Location loc
  join NonSerialized ns on ns.ID = loc.ID

Answer 3

为避免多次加入Location ，您可以将UNION ALL放在派生表中

select
  loc.Id,
  loc.locationId,
  s.ProductId,
  s.SerialNumber,
  s.Quantity   
from Location loc
inner join (
    select
      s.locationId,
      s.SerialNumber,
      null as Quantity
    from Serialized s
    union all
    select
      ns.locationId,
      null,
      ns.Quantity
    from nonSerialized ns
) s on loc.LocationId = s.locationId
where loc.Id = 1;