SQL & PL/SQL

hi,

This is my query.

Transaction Table

Amount Debit Ac Credit A/C
6000 101 34
2000 29 101
3000 102 29
1000 101 39
1000 45 101
5000 34 102
1000 22 101

As u can see accountid 101 has 2 entries as debitAc.
So the debit sum is 7000. Similarly it has 3 entries
as credit A/c summing up 4000. So the balance is
7000-4000=3000 for accountid 101. I want this balance.

I tried like this.

select sum(amount) from transaction where debitac=101;
select sum(amount) from transaction where creditac=101;
then got the subtracted value as balance.

Here I have to find balances for accountids like
101,102,etc.

For all such available accountids i made a while loop
to find the sum as debitac and creditac and then
balance(by subtracting) for each accountid.

I dont want to use queries inside while loop. I may be
in need of finding balances for 8 to 10 such
accountids 101, 102, ..., 108 (not necessary in
sequence order) for a single web page.

so I want this in a single query.

Pls reply as soon as possible.