SQL Server 2017

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create table #temp (id int, amount int)
insert into #temp values (1, 100)
insert into #temp values (2, -10)
insert into #temp values (3, 50)
insert into #temp values (5, 20)
insert into #temp values (6, -20)
5 rows affected

select sum(case when amount>0 then amount end) as positive,
sum(case when amount<0 then amount end) as negetive
from #temp


positive
negetive


170
-30


Warning: Null value is eliminated by an aggregate or other SET operation.


select tempid from 
(select *,row_number() over(order by id) as tempid
from #temp) a left join #temp on a.tempid=#temp.id
where #temp.id is null


tempid


4