Updating Data, Getting User ID?

[eluser]CroNiX[/eluser]
Just a security concern with that, which may or may not apply to you. If you are passing along the user_id in your form and using that to update your records, it means that anyone with access to that form can change that user_id value in the form and overwrite stuff they may not, or should not, have permission for.

If you are using some sort of authentication where you are logging people in and storing the current user's data in session, I would use that data for retrieving the current users user_id instead of passing it around in a form, unless it doesn't apply to your case. All form/post values can be manipulated by the user using the browsers javascript console, among other ways, before submitting the form.