Implementation Guide for Oracle Self-Service E-Billing > Customizing Payment >

Avoiding Paying a Bill More Than Once

By default, Oracle Self-Service E-Billing Payment allows a bill to be paid more than once. If you want to ensure that a bill can only be paid once, then add a unique key constraint on the bill_id field of the check_payments table. You can run the set_unique_bill_id.sql script located in the EDX_HOME/payment/db/ directory to set the unique constraint. In the path, EDX_HOME is the directory where you installed Oracle Self-Service E-Billing. Note, the bill_id in Oracle Self-Service E-Billing Payment is the same as the doc ID in the Command Center.

If a customer tries to pay a bill that has already been paid (either from the UI or by a previously scheduled recurring payment) after the unique key constraint has been added, then an error message displays indicating that the bill has been already paid. If the bill is paid from the UI and a recurring payment tries to pay it again, then the payment will fail and an email notification message will be sent to the customer (if recurring payments are configured for that email notification).

Adding this constraint will not prevent a customer from making a payment using a bill ID. For example, a customer can still make a payment directly from the Make Check Payment link, which allows him or her to make a payment without specifying a bill.

The unique key constraint only informs customers that the bill has been paid when they try to pay a bill that has already been paid. If you want to provide additional features, such as disabling the payment button when the bill has already been paid, then you must query the database to get that information. Be careful when adding extra functions, because performing additional database queries can affect Oracle Self-Service E-Billing Payment performance. Make sure the proper index has been created if you plan to create a new query.