最新客戶捐贈，金額

Question

我有兩個表：

1. Customer其中具有代表客戶ID的Id列。
2. CustomerDonation包含CustomerId（FK），Amount和DatePayed

我想擁有所有的客戶連同其最新的捐款和捐款金額。

我在我的查詢中收到重複值，因此我不會將其粘貼到此處。

Answer 1

WITH 
    SortedDonation AS 
(
    SELECT 
     ROW_NUMBER() OVER (PARTITION BY CustomerId ORDER BY DatePayed DESC) AS SeqID, 
     * 
    FROM 
     CustomerDonation 
) 
SELECT 
    * 
FROM 
    Customer 
LEFT JOIN 
    SortedDonation 
     ON SortedDonation.CustomerId = Customer.Id 
     AND SortedDonation.SeqId  = 1 

如果相同的客戶可以進行多次捐款與同DatePayed，那麼這將隨便挑只是其中之一。

如果您向ORDER BY添加其他字段，您可以確定性地選擇您想要的字段。

或者，如果你希望所有的人都使用DENSE_RANK()代替ROW_NUMBER()

Answer 2

使用Row_Number（）分析函數。

Select * from (
    Select customerId,Amount,DatePayed, row_number() over (partition by CustomerId order by DatePayed desc) as rowN) 
    as tab where rowN = 1 

Answer 3

您只需要CustomerDonation就可以了。如果您需要客戶的其他信息，您可以加入Customer表。

WITH cte AS (
SELECT 
    CustomerId 
    , MAX(DatePayed) AS LastDate 
FROM 
    CustomerDonation 
) 
SELECT 
    cd.CustomerId 
    , cd.Amount 
    , cd.DatePayed 
FROM 
    CustomerDonation cd 
    JOIN cte ON cd.CustomerId = cte.CustomerId 
     AND cd.DatePayed = cte.LastDate 

Answer 4

你也可以使用WITH TIES選項

Select Top 1 With Ties * 
    From YourTable 
    Order By Row_Number() over (Partition By CustomerId Order By DatePayed Desc)