hebisr,
I don't know crap about Dreamweaver, but if you're using a login/password with phpMyAdmin that works for logging in, I see no reason you shouldn't be able to use it elsewhere.
Just a forewarning, there are different types of logins for MySQL DB's. There's full-access, write/read, and read-only logins. Should you use a full-access login in your code and someone by chance gets it, it won't be pretty if they use it maliciously.
Hope this helps in some way,
Tom 🙂