sqlserver重複データをフィルタするsql文について

--       (     )
/******************************************************************************************************************************************************
1、Num、Name        ,           
2、Name  ,ID      ,           
   ：   (Roy)
******************************************************************************************************************************************************/

--1、          (          2000            ,SQL2005 row_number    )

--> --> (Roy)      

if not object_id('Tempdb..#T') is null
    drop table #T
Go
Create table #T([ID] int,[Name] nvarchar(1),[Memo] nvarchar(2))
Insert #T
select 1,N'A',N'A1' union all
select 2,N'A',N'A2' union all
select 3,N'A',N'A3' union all
select 4,N'B',N'B1' union all
select 5,N'B',N'B2'
Go


--I、Name  ID     (   1,2,3),  3 SQl05 ，    1、2
  1:
Select * from #T a where not exists(select 1 from #T where Name=a.Name and ID=b.ID group by a.ID,a.Name,a.Memo having count(1)=1 

  5:
select * from #T a group by ID,Name,Memo having ID=(select min(ID)from #T where Name=a.Name)

  6:
select * from #T a where (select count(1) from #T where Name=a.Name and IDall(select ID from #T where Name=a.Name)

  9( :ID      ):
select * from #T a where ID in(select min(ID) from #T group by Name)

--SQL2005:

  10:
select ID,Name,Memo from (select *,min(ID)over(partition by Name) as MinID from #T a)T where ID=MinID

  11:

select ID,Name,Memo from (select *,row_number()over(partition by Name order by ID) as MinID from #T a)T where MinID=1

    :
/*
ID          Name Memo
----------- ---- ----
1           A    A1
4           B    B1

(2     )
*/


--II、Name  ID     , min  :
  1:
Select * from #T a where not exists(select 1 from #T where Name=a.Name and ID>a.ID)

  2:
select a.* from #T a join (select max(ID)ID,Name from #T group by Name) b on a.Name=b.Name and a.ID=b.ID order by ID

  3:
select * from #T a where ID=(select max(ID) from #T where Name=a.Name) order by ID

  4:
select a.* from #T a join #T b on a.Name=b.Name and a.ID<=b.ID group by a.ID,a.Name,a.Memo having count(1)=1 

  5:
select * from #T a group by ID,Name,Memo having ID=(select max(ID)from #T where Name=a.Name)

  6:
select * from #T a where (select count(1) from #T where Name=a.Name and ID>a.ID)=0

  7:
select * from #T a where ID=(select top 1 ID from #T where Name=a.name order by ID desc)

  8:
select * from #T a where ID! --> (Roy)      

if not object_id('Tempdb..#T') is null
    drop table #T
Go
Create table #T([ID] int,[Name] nvarchar(1),[Memo] nvarchar(2))
Insert #T
select 1,N'A',N'A1' union all
select 2,N'A',N'A2' union all
select 3,N'A',N'A3' union all
select 4,N'B',N'B1' union all
select 5,N'B',N'B2'
Go

--I、Name  ID     (   1,2,3),      
  1:
delete a from #T a where  exists(select 1 from #T where Name=a.Name and ID0

  6:
delete a from #T a where ID<>(select top 1 ID from #T where Name=a.name order by ID)

  7:
delete a from #T a where ID>any(select ID from #T where Name=a.Name)



select * from #T

    :
/*
ID          Name Memo
----------- ---- ----
1           A    A1
4           B    B1

(2     )
*/


--II、Name  ID         :

  1:
delete a from #T a where  exists(select 1 from #T where Name=a.Name and ID>a.ID)

  2:
delete a  from #T a left join (select max(ID)ID,Name from #T group by Name) b on a.Name=b.Name and a.ID=b.ID where b.Id is null

  3:
delete a from #T a where ID not in (select max(ID) from #T where Name=a.Name)

  4( :ID      ):
delete a from #T a where ID not in(select max(ID)from #T group by Name)

  5:
delete a from #T a where (select count(1) from #T where Name=a.Name and ID>a.ID)>0

  6:
delete a from #T a where ID<>(select top 1 ID from #T where Name=a.name order by ID desc)

  7:
delete a from #T a where ID --> (Roy)      

if not object_id('Tempdb..#T') is null
    drop table #T
Go
Create table #T([Num] int,[Name] nvarchar(1))
Insert #T
select 1,N'A' union all
select 1,N'A' union all
select 1,N'A' union all
select 2,N'B' union all
select 2,N'B'
Go

  1:
if object_id('Tempdb..#') is not null
    drop table #
Select distinct * into # from #T--              #

truncate table #T--   

insert #T select * from #    --    #    #T 

--    
select * from #T

/*
Num         Name
----------- ----
1           A
2           B

(2     )
*/

--            2
  2:

alter table #T add ID int identity--     
go
delete a from  #T a where  exists(select 1 from #T where Num=a.Num and Name=a.Name and ID>a.ID)--       
go
alter table #T drop column ID--     

--    
select * from #T

/*
Num         Name
----------- ----
1           A
2           B

(2     )

*/

--            3
  3:
declare Roy_Cursor cursor local for
select count(1)-1,Num,Name from #T group by Num,Name having count(1)>1
declare @con int,@Num int,@Name nvarchar(1)
open Roy_Cursor
fetch next from Roy_Cursor into @con,@Num,@Name
while @@Fetch_status=0
begin 
    set rowcount @con;
    delete #T where Num=@Num and Name=@Name
    set rowcount 0;
    fetch next from Roy_Cursor into @con,@Num,@Name
end
close Roy_Cursor
deallocate Roy_Cursor

--    
select * from #T
/*
Num         Name
----------- ----
1           A
2           B

(2     )
*/