Just to let you all know, I'm a beginner at PHP and MySQL...

anyways, I figured out how to insert member signup info(username, password, email, address, etc..) into my table MEMBER_LIST. However, I want to make sure that there is no duplicate members, that someone doesn't signup twice. I'm limiting the duplication check to username, email, and first name + last name(together). My question is how do I program this? just the duplication check?

let me know if I can clear anything up further, thanks,