OVER ORDER BY

Question

有多個列在OVER ORDER BY子句中是否有指定多個列的方法？

SELECT ROW_NUMBER() OVER(ORDER BY (A.Col1)) AS ID FROM MyTable A 

上述工作正常，但試圖添加第二列不起作用。

SELECT ROW_NUMBER() OVER(ORDER BY (A.Col1, A.Col2)) AS ID FROM MyTable A 

附近有語法錯誤 ''。

Answer 1

問題是圍繞列名稱的額外括號。這些都應該工作：

-- The standard way 
SELECT ROW_NUMBER() OVER(ORDER BY A.Col1) AS ID FROM MyTable A 
SELECT ROW_NUMBER() OVER(ORDER BY A.Col1, A.Col2) AS ID FROM MyTable A 

-- Works, but unnecessary 
SELECT ROW_NUMBER() OVER(ORDER BY (A.Col1), (A.Col2)) AS ID FROM MyTable A 

此外，當您問一個SQL問題時，您應該始終指定您查詢哪個數據庫。

Answer 2

沒有括號。

SELECT ROW_NUMBER() OVER(ORDER BY A.Col1, A.Col2) AS ID FROM MyTable A 

Answer 3

這是不可能的Row_Num 你可以看到語法：

ROW_NUMBER () 
    OVER ([ PARTITION BY value_expression , ... [ n ] ] order_by_clause) 

如果使用額外的順序由申請在GROUP BY你可以做到這一點..