如何從我的表中選擇不同的列？

Question

我有兩張工作表。第一張表#CustomerList我手動初始化值。然後我創建第二個表#CustomerListWithRank_Id，它基於第一個表#CustomerList。

第一和第二臺之間的唯一不同的是，第二個表#CustomerListWithRank_Id有一欄，讓每一個它的ROWNUMBER我用進一步下跌在我的SQL代碼時，我遍歷該錶行。

所以我的問題是，我只是想初始化#CustomerListWithRank_Id只有來自列[FileName]的唯一值，我該怎麼做？

SELECT '3004' Customer_No,'831001' DDD_Reference_No,'varer831.csv' [FileName] 
INTO #CustomerList -- DROP TABLE #CustomerList 
UNION ALL SELECT '3002' Customer_No,'199001' DDD_Reference_No,'varer199.csv' [FileName] 
UNION ALL SELECT '3003' Customer_No,'199002' DDD_Reference_No,'varer199.csv' [FileName] 

-

SELECT *, ROW_NUMBER() OVER (ORDER BY Customer_No) AS 'Rank_Id' 
INTO #CustomerListWithRank_Id --DROP TABLE #CUstomerListWithRank_ID 
FROM #CustomerList 

如果我使用GROUP BY [文件名]在上面的查詢我得到這個錯誤：

Msg 8120, Level 16, State 1, Line 1 
Column '#CustomerList.Customer_No' is invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause. 

Answer 1

這是你需要什麼？

select *, ROW_NUMBER() OVER (ORDER BY Customer_No) AS 'Rank_Id' 
INTO #CustomerListWithRank_Id 
from 
(
    SELECT max(Customer_No) Customer_No, max(DDD_Reference_No) DDD_Reference_No, FileName 
    FROM #CustomerList 
    group by FileName 
) t 

Answer 2

這是你所需要的

SELECT * INTO #CustomerListWithRank_Id From 
(SELECT *, ROW_NUMBER() OVER (PARTITION BY FileName Order by Customer_No) AS RowNum FROM CustomerList)