As part of a series of useful, simple queries for Oracle Receivables, here is a simple query to find open receivables invoices. There are many other additions you can make to the query to more accurately specify what you are looking for. This is meant to get you off the ground.
If you need help constructing a more specific, feel free to comment below!
select aps.* from ar_payment_schedules_all aps, hz_cust_accounts hca where aps.customer_id = hca.cust_account_id and aps.class = 'INV' and aps.status = 'OP' and hca.account_number = 'Customer Number Here' order by aps.last_update_date desc
The same information this query returns can be found using Transactions Summary in the Recievables Manager responsibility.