row_number（）記錄范圍內的SQL Server唯一記錄

Question

SELECT
*
FROM (
    SELECT      
        row_number() OVER (ORDER BY ID) AS [rownum],
        UserID, wfoKey 
    FROM
        tbl_user_statistics2 Where (wfoKey = '4b1fbf7aa7')
) T
WHERE 
rownum BETWEEN (@opt_start) AND (@opt_end) 

上面的查詢有效，並將所有用戶ID從第1行（opt_start）拉到10,000（opt_end）。 在該數據集中，那些UserID是重復的。 我現在想為該行范圍（1到10,000）中的記錄提取唯一的UserID。 用戶可以選擇任意范圍，因此可以選擇10,0000到20,0000，因此查詢應獲取該范圍內的唯一UserID，依此類推。 我不需要結果中的rownum。

樣本數據：

1   dced6f0d-3a67-456d78cb7-fb73c8db0c13    4b1fbf7aa7
2   dced6f0d-3a67-456d78cb7-fb73c8db0c13    4b1fbf7aa7
3   6360f485-4f4d-4c9a98b0e-74fea312a25d    4b1fbf7aa7
4   6360f485-4f4d-4c9a98b0e-74fea312a25d    4b1fbf7aa7

結果將是：

dced6f0d-3a67-456d78cb7-fb73c8db0c13    4b1fbf7aa7
6360f485-4f4d-4c9a98b0e-74fea312a25d    4b1fbf7aa7

不知道如何繼續，或者可能有比row_number（）更好的方法。 任何建議將不勝感激。

Answer 1

可以通過采用現有查詢並將其轉換為嵌入式視圖（ T2 ），然后從中查詢不同的記錄來解決此問題：

SELECT DISTINCT UserID, wfoKey FROM
(SELECT
*
FROM (
    SELECT      
        row_number() OVER (ORDER BY ID) AS [rownum],
        UserID, wfoKey 
    FROM
        tbl_user_statistics2 Where (wfoKey = '4b1fbf7aa7')
) T
WHERE 
rownum BETWEEN (@opt_start) AND (@opt_end)) T2 

Answer 2

;With CTE1
AS
 (
 SELECT * , rn = ROW_NUMBER() OVER (PARTITION BY UserID ORDER BY wfoKey)
 FROM tbl_user_statistics2 
 Where wfoKey = '4b1fbf7aa7'
 ),
 CTE2
 AS
 (
  SELECT ID, UserID, wfoKey 
       , RowNum = ROW_NUMBER() OVER (ORDER BY wfoKey)
  FROM CTE1 
  WHERE rn = 1 
  )
SELECT ID, UserID, wfoKey 
FROM CTE2
WHERE RowNum BETWEEN (@opt_start) AND (@opt_end) 

Answer 3

您可以通過userID添加一個名為partition的片段

    ;with cte as(
    SELECT
    *
    FROM (
        SELECT      
            row_number() OVER (partition by USerID ORDER BY ID) AS [rownum],
            UserID, wfoKey 
        FROM
            tbl_user_statistics2 Where (wfoKey = '4b1fbf7aa7')
    ) T
    WHERE 
    rownum BETWEEN (@opt_start) AND (@opt_end) 
    )

    Select * from cte
    where rownum =1