【】怎么UPDATE两条完全相同的记录

【高手进】如何UPDATE两条完全相同的记录？
现在有2条完全相同的记录，但是我只想UPDATE其中的一条。
不想删除数据。
请高手解答
谢谢

[解决办法]

SQL code

;WITH Liang AS (    SELECT * ,rowid=ROW_NUMBER() OVER(PARTITION BY xx ORDER BY id)    FROM tb)UPDATE Liang SET    xx = xxWHERE rowid = 1;
[解决办法]
SQL code
UPDATE TOP(1) tb SET   xx=xxWHERE xx=xxx
[解决办法]
SQL code
--借助一个子增列alter table tb add id int identity(1,1)go--更新需要更新的那个update tb set col=.... where id=..go--去掉该子增列alter table tb drop column id
[解决办法]
SQL code
DECLARE @T TABLE(COL1 VARCHAR(10))INSERT INTO @TSELECT 'A' UNION ALLSELECT 'A'UPDATE TOP(1) @T SET COL1='B' WHERE COL1='A'SELECT * FROM @T/*BA*/
[解决办法]
SQL code
create table test_top(id int, name varchar(10))insert into test_topselect '1','aa' union allselect '1','aa'1种set rowcount 1update test_top set name='tt'set rowcount 02种;with ttttt as (    select * , row = row_number() over (order by id ) from test_top)update ttttt set name='x' where row =1
[解决办法]
SQL code
-- =========================================-- -----------t_mac 小编-------------   ---希望有天成为大虾---- -- =========================================IF OBJECT_ID('tb') IS NOT NULL  DROP TABLE tbGOCREATE TABLE tb(a int,b int)goinsert into tbselect 1,2 union allselect 1,2 goset rowcount 1update tb set a=3,b=5where a=1 and b=2set rowcount 0select  * from tb/*------------a           b----------- -----------3           51           2-------*/
[解决办法]
你用的是SQL Server 2000吧？

那么
SQL code
 row_number、 update top (1)
[解决办法]
SQL> select *
 2  from t
 3  ;

        A B
---------- -----
        1 a
        1 a
        2 c


SQL> update t
 2  set b='b'
 3  where rowid=(select min(rowid) from t where a=1 and b='a')
 4  ;

已更新 1 行。

SQL> select *
 2  from t
 3  ;

        A B
---------- -----
        1 b
        1 a
        2 c
[解决办法]
SQL code
--2005方法 -- =========================================-- -----------t_mac 小编-------------   ---希望有天成为大虾---- -- =========================================IF OBJECT_ID('tb') IS NOT NULL  DROP TABLE tbGOCREATE TABLE tb(a int,b int)goinsert into tbselect 1,2 union allselect 1,2 goupdate top(1) tb set a=3,b=5where a=1 and b=2select * from tb (1 行受影响)a           b----------- -----------3           51           2--2000方法-- =========================================-- -----------t_mac 小编-------------   ---希望有天成为大虾---- -- =========================================IF OBJECT_ID('tb') IS NOT NULL  DROP TABLE tbGOCREATE TABLE tb(a int,b int)goinsert into tbselect 1,2 union allselect 1,2 goset rowcount 1update tb set a=3,b=5where a=1 and b=2set rowcount 0select  * from tb/*------------a           b----------- -----------3           51           2-------*/
[解决办法]
SQL code 
 
-->生成测试数据:if not object_id('tb') is null  drop table tbgocreate table tb(col varchar(10))goinsert tbselect 'a' union allselect 'a' union allselect 'b' union allselect 'b'go-->SQL2000查询如下: declare @col varchar(10),@newcol varchar(10)update tb set     col=@newcol,    @newcol=case when col=@col then col             else 'new-'+col        end,    @col=colselect * from tb/*col----------new-aanew-bb(4 行受影响)*/