利用存储过程来消弭数据库中冗余的数据
CREATE PROCEDURE sp_mytest AS
declare @pro varchar(50)
declare @mm int
declare wu Cursor for select distinct product from mytest
open wu
fetch next from wu into @pro
while @@fetch_status=0
begin
 select @mm=sum([cost]) from mytest where [product]=@pro
 delete from mytest where [product]=@pro
 insert into mytest ([product],[cost]) values(@pro,@mm)
 
 fetch next from wu into @pro
end
close wu
deallocate wu
GO
我们可以使用作业进行相应的数据的更新