Question

我无法将以下选择查询更改为更新查询。请有人帮忙

SELECT 
CONVERT(varchar(10), (ROW_NUMBER() over (order by (select null)))) + 'Test@' +(SELECT SUBSTRING(Email, CHARINDEX('@', Email) + 1, LEN(Email) - CHARINDEX('@', Email))) as Email
,CONVERT(varchar(10), (ROW_NUMBER() over (order by (select null)))) + 'Media' as [Last Name]
from dbo.MPP_Inserts as MT

我已尝试过以下内容但收到错误消息：

窗口函数可以通过子句出现在选择或顺序中）

Update dbo.MPP_Inserts
Set Email = CONVERT(varchar(10), (ROW_NUMBER() over (order by (select null)))) + 'Test@' +(SELECT SUBSTRING(Email, CHARINDEX('@', Email) + 1, LEN(Email) - CHARINDEX('@', Email)))
, [Last Name] = CONVERT(varchar(10), (ROW_NUMBER() over (order by (select null)))) + 'DMG Media'

Answer 1

看起来您正在使用SQL Server。如果是这样，您有可更新的CTE：

with toupdate as (
    SELECT mt.*,
           CONVERT(varchar(10), (ROW_NUMBER() over (order by (select null)))) + 'Test@' +(SELECT SUBSTRING(Email, CHARINDEX('@', Email) + 1, LEN(Email) - CHARINDEX('@', Email))) as new_Email,
           CONVERT(varchar(10), (ROW_NUMBER() over (order by (select null)))) + 'Media' as new_lastname
    from dbo.MPP_Inserts MT
   )
update toupdate
    Set Email = new_email,
       [Last Name] = new_lastname;

子串中的嵌套select是完全没必要的，但我保留了表达式不变，因此它们与查询中的相同。但是，new_email可以表示为：

CONVERT(varchar(10), (ROW_NUMBER() over (order by (select null)))) + 'Test@' +SUBSTRING(Email, CHARINDEX('@', Email) + 1, LEN(Email) - CHARINDEX('@', Email)) as new_Email,

将选择查询更改为更新

1 个答案: