SELECT 编号B ORDER BY REPLACE(编号B,'-','')*1 DESC

------解决方案--------------------

SQL code
SELECT 编号B ORDER BY CAST(replace(编号B,'-','')AS INT) DESC

------解决方案--------------------
SQL code

declare @T table([ID] int,[编号B] varchar(12))
insert @T
select 1,'2012-08-68' union all
select 2,'2012-06-36' union all
select 3,'2012-12-1002' union all
select 4,'2012-12-985'

select * from @T 
ORDER BY LEFT([编号B],8),SUBSTRING([编号B],9,LEN([编号B])-8)*1 
/*
ID          编号B
----------- ------------
2           2012-06-36
1           2012-08-68
4           2012-12-985
3           2012-12-1002
*/