Finding all unapplied receipts in AR

Select a.cash_receipt_id, a.receipt_number, a.Amount, SUM(b.AMOUNT_APPLIED) AS “Unapplied”
from apps. AR_CASH_RECEIPTS_ALL a,
apps. AR_RECEIVABLE_APPLICATIONS_ALL b
WHERE a.ORG_ID=’118′
AND a.CURRENCY_CODE=’USD’
AND a.cash_receipt_id=b.cash_receipt_id
AND b.STATUS=’UNAPP’
GROUP BY a.cash_receipt_id, a.receipt_number, a.Amount