Complete Form Dynamically

Goal: Have visitor enter data into the first field of a form. Then onchange have additional fields on the form be auto-completed if there is a match in the database. I do not want the entire page to be refreshed to get the data. On submit all fields will be sent to the database. It is okay if there is no original user_ID in the database, if the person reaching the form enters something in that field that doesn't match, we'll just create a new record with the data from all three fields. If there was a match, on submission it will simply update the original record for that user_ID. The goal is the have the user_ID never duplicated. The attached html form gives you a simple example of the initial form. And I've attached a simple [login to view URL] file to give you database concept. I don't need anything to look fancy. Here is my concept of flow: 1. [login to view URL] (or actually [login to view URL]) 2. on user_ID field change we could utilize AJAX / Javascript to call a [login to view URL] page which does the database lookup to see if the user_ID exists 3. data from database is parsed using javascript or JSON and returned to the [login to view URL] 4. data is placed into specific text boxes of [login to view URL] (the real application will have more than just first and last names) 5. on submit the [login to view URL] processes the data back into the database (updating user_ID if originally found, or adding to the database a new manually created user_ID) My current server: php5.2.x, mysql 4.x, json 1.2.1 Please plan on making a [login to view URL], [login to view URL], [login to view URL], sql file (or update mine) and any associated files you feel will be needed. Cross browser compatible is a must, IE, Firefox, Safari, as many as possible. Alternatives to my concept are welcomed as long as they update the page data instantly. Please specify any technology that you are planning to use when you post your bid. IE: php, javascript, ajax. This way I can check to ensure our server can be used with your solution. We have payment escrolled in [login to view URL] already so I'm looking for an efficient solution. Thanks in advance, Q3