>> SELECT (SELECT sum(amount) FROM table WHERE debit=X) AS debit, (SELECT
>> sum(amount) FROM table WHERE credit=x) AS credit;
>
> If most of the records are credits or debits you don't want to do this.
> A single sequential scan through the table will be the best plan.
I thought that debit = source account # and credit = dest account #, and
there are a lot of different account...