sql - OVER ORDER BY 中的多个列

Question

有没有办法在 OVER ORDER BY 子句中指定多个列？

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

以上工作正常，但尝试添加第二列不起作用。

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

Incorrect syntax near ','.

Answer 1

问题是列名周围有多余的括号。这些应该都有效:

-- 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，当您提出 SQL 问题时，您应该始终指定要查询的数据库。