SQL - JOIN问题

时间:2018-06-07 20:36:52

标签: sql sql-server join

我有两张表F和表D.

表F提供了有关账户金融交易的详细信息(付款,收费,利息......) 表D显示了拖欠状态(如果用户未付款)。它显示了不同的状态代码。 0,1,2,11(意思是不同的东西)

我的表格结构如下:

Table F
============
------------------------------------------- 
|AccountId|TypeCode |BusinessDate|TransAmt|
------------------------------------------- 
|12345    | PYMT    |2016-06-22  |   10.54|
------------------------------------------- 
|12345    | TOLL    |2016-06-15  |   04.00|
------------------------------------------- 
|12345    | INTR    |2016-05-26  |   01.66|
------------------------------------------- 
|12345    | TOLL    |2016-04-10  |   04.00|
------------------------------------------- 

Table D
==========
-----------------------------------------------
|AccountId|FromID|ToID|CreatedDate            |
----------------------------------------------- 
|12345    |     0|   2|2016-12-25 00:12:44.453|
----------------------------------------------- 
|12345    |     2|   1|2017-04-02 07:16:46.770|
----------------------------------------------- 
|12345    |     1|  11|2017-07-12 16:16:36.747|
-----------------------------------------------

我正在尝试运行代码以查找帐户进入状态码11(ToID)后帐户上所有付款的总和

我的代码:

SELECT F.AccounttID
      ,ISNULL(SUM(TransAmt), 0) Payments

FROM F INNER JOIN D ON F.AccounttID = D.AccountId

WHERE AccountId = 12345   
  AND TypeCode = 'PYMT'   
  AND F.BusinessDate >= D.CreatedDate  
  AND ToID = 11 
--AND F.BusinessDate >= (SELECT CreatedDate FROM D WHERE F.AccounttID = D.AccountId AND ToID = 11)    

GROUP BY F.AccountID, F.TypeCode

我得到的结果是:

--------------------
|AccountID|Payments|
--------------------
|         |        |
--------------------

我想要的结果是:

--------------------
|AccountID|Payments|
--------------------
|   12345|     0.00|
--------------------

2 个答案:

答案 0 :(得分:1)

删除GROUP BY

SELECT MAX(F.AccounttID) as AccounttID,
       COALESCE(SUM(TransAmt), 0) Payments
FROM F INNER JOIN
     D
     ON F.AccounttID = D.AccountId
WHERE AccountId = 12345 AND 
      TypeCode = 'PYMT' AND  
      F.BusinessDate >= D.CreatedDate AND
      ToID = 11 
--AND F.BusinessDate >= (SELECT CreatedDate FROM D WHERE F.AccounttID = D.AccountId AND ToID = 11)    

这似乎违反直觉。但是,即使所有行都被过滤掉,也确保没有GROUP BY的聚合查询只返回一行。使用GROUP BY,聚合查询每组返回一行。如果过滤掉所有行,则不返回任何行。

答案 1 :(得分:1)

您的问题是您的where条件没有匹配结果。我认为你实际上是想使用conditional aggregation。我还使用了outer join,以防无法匹配:

SELECT F.AccounttID
      ,SUM(CASE WHEN F.BusinessDate >= D.CreatedDate THEN F.TransAmt ELSE 0 END) Payments
FROM F 
    LEFT JOIN D ON F.AccounttID = D.AccountId AND D.ToId = 11
WHERE F.AccountId = 12345   
    AND F.TypeCode = 'PYMT'   
GROUP BY F.AccountID