add promo code option

We have a webform [login to view URL] and we would like another field added labelled PROMO CODE. this field will take a users promo code, and compare it to a list of codes stored in the SQL database, if the code exists, it marks it as used, then awards the user which registered 30 minutes or whatever the code is for. we already have a system which tracks minutes for users and things. So really only thing being added is collecting the promo code on the form, checking its validity, and then awarding the minutes to the users. ## Deliverables 1) Complete and fully-functional working program(s) in executable form as well as complete source code of all work done. 2) Deliverables must be in ready-to-run condition, as follows (depending on the nature of the deliverables): a) For web sites or other server-side deliverables intended to only ever exist in one place in the Buyer's environment--Deliverables must be installed by the Seller in ready-to-run condition in the Buyer's environment. b) For all others including desktop software or software the buyer intends to distribute: A software installation package that will install the software in ready-to-run condition on the platform(s) specified in this bid request. 3) All deliverables will be considered "work made for hire" under U.S. Copyright law. Buyer will receive exclusive and complete copyrights to all work purchased. (No GPL, GNU, 3rd party components, etc. unless all copyright ramifications are explained AND AGREED TO by the buyer on the site per the coder's Seller Legal Agreement). ## Platform PHP SQL database