update a 
set col3 = col3 + (select sum(col3) from ta where a.col2  = col1) 
from ta a 

delete a from ta 
where exists(select 1 from ta where col1 = a.col2)

declare @tab table
(字段1 varchar(20) null,
 字段2 varchar(20) null,
 字段3 int null)
insert into @tab(字段1,字段2,字段3)select 字段2,字段1,字段3 from 表A

delete from 表A
from 表A as a
inner join @tab as b
on a.字段1 = a.字段2 and a.字段2 = b.字段1

update 表A
set 字段3 = 字段3 +  b.字段3
from 表A as a
inner join @tab as b
on a.字段1 = a.字段1 and a.字段2 = b.字段2

select 字段1,
(select top 1 (字段2) from 表A as b where a.字段1=b.字段1) as 字段2,
(select sum(字段3) from 表A as b where a.字段1=b.字段1 order by 字段1 asc) as 字段3
 from 表A as a 
group by 字段1