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HomeDatabaseMysql Tutorial在SQL 2005中实现循环每一行做一定的操作_MySQL

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    在SQL 2005中实现循环每一行做一定的操作
2009-03-05 16:00   来源:不详   作者:佚名 RSS复制链接打印核心提示:如果我们想对一个表的每一行做出比较复杂的操作,大多会想到用游标,本文中,我们将换一种思路,用SQL Server 2005中的新函数ROW_NUMBER()和while循环来对每一行执行操作。详细的示例代码如下:

如果我们想对一个表的每一行做出比较复杂的操作,大多会想到用游标,本文中,我们将换一种思路,用SQL Server 2005中的新函数ROW_NUMBER()和while循环来对每一行执行操作。详细的示例代码如下:
 

      select Department_No as departmentNo,ROW_NUMBER()

OVER(ORDER BY Department_No) AS rowNumber into

#depTemp--建立临时表
from departments

declare @max int
--用来获得最大的rowNumber
select @max=max(rownumber)
from #depTemp

declare @rowNo int
set @rowNo=1
while @rowNo--用来对每一个rowNumber来进行循环操作
begin
--此处对每一行要进行的操作的代码
set @rowNo=@rowNo+1
end
drop table #depTemp--清除临时表

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