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drop table atzk
go
create table atzk
(
  nid int identity(1,1) primary key,--nid×Ô¶¯±àºÅ£¬²¢ÉèΪÖ÷¼ü¡£
  mytitle varchar(50) not null,--֪ͨµÄ±êÌâ¡£
  mycontents varchar(200)--·¢²¼Í¨ÖªµÄÄÚÈÝ¡£
 )


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2           ¶ÔÏóȨÏÞ£º¶ÔÊý¾ÝµÄÔö¡¢É¾¡¢¸Ä¡¢²é¡ ......

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  alter table tablename
  add city varchar£¨2£© default 'rr' //¸³Ä¬ÈÏÖµ
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  alter table tablename
  modify city varchar£¨20£©
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  alter t ......

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select *
from
(select [id]=row_number() over (order by getdate()),
        date=convert(varchar(8),dateadd(dd,number,'2010-01-01'),112)
        from
        (select number from master..spt ......
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