数据库中有关差异备份的恢复问题(1)

create  database  test  
create  table  t(a  int)  
insert  into  test..t  select  1

backup  database  test  to  disk='c:\test.bak'  
insert  into  test..t  select  2

backup  database  test  to  disk='c:\test.bak'  
insert  into  test..t  select  3

restore  database  test  from  disk='c:\test.bak'  with  file=1

restore  database  test  from  disk='c:\test.bak'  with  file=2

backup  database  test  to  disk='c:\test.bak'  with  differential

exec  master..xp_cmdshell  'del  c:\text.bak'  
if  exists(select  *  from  master..sysdatabases  where  name='test')  
drop  database  test  
go

create  database  test 
go

use  test  
go