Alternative to findAllBySql() for many_many relation

Here’s a new twist on an old chestnut… looking for any advice or guidance on what is the Yii way to handle this scenario:

I have the following relationship in the database:

tbl_account-> PK id

tbl_invoice -> PK id

tbl_payment -> PK id

tbl_account_invoices_payments PK (account_id, invoice_id, payment_id)

I have models for Account, Invoice, Payment but not for tbl_account_invoice_payment.

Right now in the Invoice model I have this code to return all the invoice objects that match to a specific account_id and payment_id:

$sql = "SELECT invoice_id FROM tbl_account_invoice_payment WHERE account_id=':accountId 'AND payment_id=':paymentId'";


return self::model()->findAllBySql($sql, $params);

I dont think this will work, and it feels so…well…dirty! :unsure: is there a better way?

How can I get a set of filtered invoice objects back from the return value?

[size="1"](I like the idea of setting up a HAS_MANY , through relationship in the model, but dont need the overhead of another model class for the relational table.)[/size]