SQL & PL/SQL

Hello,

Would anybody know if this is possible at all? Preferably within the function without further grouping or nesting as this is a much simpified explanation of an issue I am having with a far larger and more esoteric query...

If I have a table with ID codes in column A, which are often repeated over several rows, and USD amounts in column A.

eg.

ID¦USD
1¦1,000
2¦5,000
3¦2,000
3¦2,000
3¦2,000
3¦2,000
4¦5,000
4¦5,000
5¦20,000
5¦20,000
5¦20,000

I would like to sum the USD amount in column B, but only once per unique ID in column A, ie (1000+5000+2000+5000+20000 = 33000)

I tried the following syntax to no avail;

sum(USD) over(distinct ID) ob

I am assuming that the following would count each distinct USD amount, this is not what I am looking for;

sum(distinct USD) ob

FYI here is the query shell that I am trying to use this in, the problem I have is that the ID codes in the query results i've called 'table' duplicate (correctly) IDs on occassion, I only want my counts and sums to count each ID once though. I can easily count my distinct IDs but I am not sure how get it to sum the values in the other columns based on this.

select  geo_segment_name 
      , bus_grp_typ
      , agg_grp_sctr
      , sum(original_balance_usdm) ob                   --need this for distict class_ids
      , sum(current_balance_qport_usdm) cb         --need this for distict class_ids
      , count(distinct deal_id) deal_count
      , count(distinct class_id) class_count 
from (table)
group by geo_segment_name, bus_grp_typ, agg_grp_sctr

Could anyone please advise?

In your debt!

Thanks

Jon