Admin Feature Insertion

[Rich]

I am not sure what I have been doing wrong so I am posting here.

I want to add a yes/no field to a modification I am using. What do I need to add to the admin file so that the field works and is stored? I can get the field to show with this:

    print_yes_no_row($vbphrase['shoppingcart_paymentplan'], 'paymentplan', $product['paymentplan']);

I have the phrase set obviously. The field displays as it should, where it should.

The field "paymentplan" has been added to the "products" table which is what this affects. When I click "save" after setting the value for the yes/no it doesn't save. I am guessing I am missing something completely but can't figure it out.