/**/ /*

删除表中重复行的方法

*/

if   exists ( select   1   from  sys.tables  where  name = ' t_dup ' )

     drop   table  t_dup

go

create   table  t_dup(id  int ,age  int ,name  varchar ( 32 ))

insert   into  t_dup

select   1 , 1 , ' a '

union   all   select   1 , 1 , ' a '

union   all   select   1 , 1 , ' a '

union   all   select   1 , 2 , ' a '

union   all   select   1 , 2 , ' e '

union   all   select   2 , 3 , ' b '

union   all   select   3 , 3 , ' d '

go

select   *   from  t_dup

go

with  t_all  as

    ( select  id,age,name,row_number()  over ( order   by  id)  [ num ]

      from  t_dup),

    t_max  as

    ( select  id,age,name, max (num) num

      from  t_all

      group   by  id,age,name)

select  id,name,age  from  t_all a  where   exists ( select   1   from  t_max  where  num = a.num)