使用ROW_NUMBER（）超過（PARTITION BY

Question

我有這個查詢：

SELECT  
    Reservation.*, 
    ROW_NUMBER() OVER (PARTITION BY code_bien ORDER BY (SELECT NULL)) AS RowNums 
FROM 
    Reservation  
WHERE
    RowNums = 1 

我收到此錯誤：

消息207，第16級，狀態1，第2行
無效的列名“ RowNums”。

我不知道問題出在哪里-有幫助嗎？

Answer 1

您不能直接使用RowNums，

這樣嘗試

SELECT *
FROM
(   
    SELECT  Reservation.*,ROW_NUMBER() OVER (PARTITION BY code_bien ORDER BY (SELECT NULL)) AS RowNums 
    FROM Reservation
) S  
where RowNums = 1

Answer 2

您需要使用CTE：

WITH tempData AS
(
 SELECT  Reservation.*, 
 ROW_NUMBER() OVER (PARTITION BY code_bien ORDER BY (SELECT NULL)) AS RowNums 
 FROM Reservation 
)

SELECT * FROM tempData WHERE RowNums = 1

但是，更干凈的方法是使用WITH TIES ：

SELECT TOP 1 WITH TIES *
FROM Reservation
ORDER BY ROW_NUMBER() OVER (PARTITION BY code_bien ORDER BY (SELECT NULL))

Answer 3

   SELECT t.*
    FROM
    (SELECT Reservation.*,ROW_NUMBER() OVER (PARTITION BY code_bien ORDER BY NULL ) AS RowNums 
    FROM Reservation) t  
where RowNums = 1

Answer 4

您不能直接使用它，因為它不是表中的一列。 使用CTE或派生表。

CTE

:WITH C AS (
    SELECT  Reservation.*,ROW_NUMBER() OVER (PARTITION BY code_bien ORDER BY (SELECT NULL)) AS RowNums 
)
SELECT * FROM C WHERE RowNums = 1 

Answer 5

嘗試這個

;WITH CTE AS(
SELECT  Reservation.*,
ROW_NUMBER() OVER (PARTITION BY code_bien ORDER BY (SELECT NULL)) AS RowNums
FROM Reservation)
SELECT * FROM CTE
WHERE RowNums = 1