create table A(B int)
insert into A values(1) 
insert into A values(5) 
insert into A values(-3) 
insert into A values(2) 
insert into A values(5) 
insert into A values(3) 
insert into A values(-2) 
insert into A values(-8)
create table B(B int)
go

select B , id = identity(int,0,1) into tmp from A

insert into B select 结果 from (select id = id/4 , 结果 = sum(B) from tmp group by id/4) t

select * from B

drop table A,B,tmp

/*
B           
----------- 
5
-2

（所影响的行数为 2 行）
*/