sql-server - 如何在 UPDATE 子句中使用 ROW_NUMBER()？

Question

ROW_NUMBER()仅适用于SELECT MS SQL Server 中的条款，但我想用它进行更新，如下所示:

Update MyTab Set MyNo = 123 +  ROW_NUMBER() over (Order By ID)
Where a=b;

然后我得到了类似的错误，

Windowed functions can only appear in the SELECT or ORDER BY clauses.

如何使用ROW_NUMBER()在UPDATE条款？

Answer 1

您可以使用 CTE:

;WITH RowNbrs AS (
    SELECT  ID
            , ROW_NUMBER() OVER (ORDER BY ID) AS RowNbr
    FROM    MyTab
    WHERE   a = b
)
UPDATE  t 
SET     t.MyNo = 123 +  r.RowNbr
FROM    MyTab t
        JOIN RowNbrs r ON t.ID = r.ID;