Question

我有三张桌子A，B和C.

表C

表A

ID1 Name    
1   John    
2   Jon    
3   William    
10  Willy    
15  Jack    
18  George

表B

ID2 Address    
1   abc    
2   def    
3   ghi    
10  jkl    
15  mno    
18  pqr

我需要输出，使得来自Table C的每一行都是一个接一个地来自各自的表中的相应名称，如下所示：

预期输出

ID Name  Address    
1  John  abc    
10 Willy jkl    
2  Jon   def    
15 Jack  mno    
so on...

此处ID2是foreign key。

我尝试了UNION，但它首先提供了与ID1相对应的所有记录，然后是ID2。

Answer 1

使用CTE：

;WITH CTE
AS
(
    SELECT c.ID1 As Order1, 1 as Order2, a.ID1, A.Name, b.Address
    FROM a
    INNER JOIN b
        ON a.ID1 = B.ID2
    INNER JOIN c
        ON c.ID1 = a.ID1
    UNION ALL
    SELECT c.ID1 As Order1, 2 as Order2, a.ID1, A.Name, b.Address
    FROM  a
    INNER JOIN b
        ON a.ID1 = B.ID2
    INNER JOIN c
        ON c.ID2 = a.ID1
)
SELECT ID1, Name, Address
FROM CTE
ORDER by order1, Order2

Answer 2

尝试下面

SELECT i.id, i.NAME, i.address 
FROM   (SELECT 1 A, 
               Row_number() OVER(ORDER BY i.id1) ordr, 
               ID, 
               A.NAME, 
               B.address 
        FROM   tablec i 
               INNER JOIN TableA A 
                       ON i.id1 = A.id1 
               INNER JOIN TableB B 
                       ON i.id1 = B.id2 
        UNION ALL 
        SELECT 2 A, 
               Row_number() OVER(ORDER BY i.id1) ordr, 
               i.id2 ID, 
               A.NAME, 
               B.address 
        FROM   tablec i 
               INNER JOIN TableA A 
                       ON i.id2 = A.id1 
               INNER JOIN TableB B 
                       ON i.id2 = B.id2) i 
ORDER  BY i.ordr, i.a

Answer 3

使用OUTER APPLY：

SELECT
    a.ID1 AS ID,
    a.Name,
    b.Address
FROM TableA a
INNER JOIN TableB b
    ON b.ID2 = a.ID1
OUTER APPLY(
    SELECT ID1, ID2
    FROM TableC
    WHERE
        ID1 = a.ID1
        OR ID2 = a.ID1
)c
ORDER BY
    c.ID1, a.ID1

<强> RESULT

ID          Name       Address    ID1*        ID2*
----------- ---------- ---------- ----------- -----------
1           John       abc        1           10
10          Willy      jkl        1           10
2           Jon        def        2           15
15          Jack       mno        2           15
3           William    ghi        3           18
18          George     pqr        3           18

ID1和ID2包含在结果中以供解释。

OUTER APPLY将返回TableC的匹配行，该行定义您的订单。您可以按c.ID1和a.ID1进行简单排序。

一个接一个地连接表的行

3 个答案: