自动加1的有关问题

自动加1的问题
create Table AA
(UYEAR varchar(4),UDIV varchar(1),AUID int)

2008 L 2
2008 A 3

如果输入 2009 L 
想要的结果是 2009 L 1
如果输入 2008 L
想要得结果是 2008 L 3

proc


ALTER PROCEDURE dbo.StoredProcedure2 
@UYEAR as varchar(4),
@UDIV as varchar(1),
@ERRORCODE as int output,
@AUID as int output  
AS
/* SET NOCOUNT ON */ 

Begin Transaction

SELECT @AUID=AUID FROM AA
  WHERE UYEAR = @UYEAR AND UDIV = @UDIV
   
if @@ROWCOUNT < = 0 
begin 

print 'AA'

INSERT INTO AA(UYEAR,UDIV,AUID)
  VALUES (@UYEAR,@UDIV,1)
print @@error
end
else
begin
UPDATE AA
SET UYEAR = @UYEAR,
UDIV = @DIV,
  SYOZOKU_NM = SYOZOKU_NM+1,
  WHERE UYEAR = @UYEAR and UDIV= @UDIV
print 'BB'
print @@error
end

IF @@ERROR <> 0
BEGIN
Rollback Transaction
SET @ERRORCODE = 3
RETURN
END

Commit Transaction

SET @ERRORCODE = 0

RETURN

为啥执行的结果不正确呢？
求救

[解决办法]
搞这么复杂做什么

[解决办法]

SQL code

ALTER   PROCEDURE   dbo.StoredProcedure2   @UYEAR   as   varchar(4), @UDIV     as   varchar(1), Asif exists(Select 1 FROM AA WHERE   UYEAR  =   @UYEAR   AND   UDIV   =   @UDIV )  Select UYEAR,UDIV,AUID+1 FROM AA WHERE   UYEAR  =   @UYEAR   AND   UDIV   =   @UDIVelse  Select 'UYEAR'=@UYEAR,'UDIV' =@UDIV,'AUID'=1
[解决办法]
SQL code
create   Table   AA (UYEAR   varchar(4),UDIV   varchar(1),AUID   int) ------------------------------搞那么复杂？create proc wsp@uyear varchar(4),@udiv varchar(1)as      if exits(select 1 from AA where uyear=@year and udiv=@udiv)              update aa set auid=auid+1 where uyear=@year and udiv=@udiv       else              insert into aa select @uyear,@udiv,1
[解决办法]
好的，呵呵  
不过还有一个问题。  
因为我这个自动加1，是要实现派他操作的。  
如果没有   Transaction的话，会不会出现同一时间更新操作呢？  

我的AUID就是想实现银行账户的流水号，不管谁操作，都不能重复。
--------------------
if exits(select 1 from AA where uyear=@year and udiv=@udiv)
             update aa set auid=auid+1 where uyear=@year and udiv=@udiv  
     else
             insert into aa select @uyear,@udiv,1


一次只有一个DML语句在执行,一个DML语句默认就是一个Transaction
所以不会的