codeigniter function error not working user id

Question

Hi I have a little issue with my functions in my libraries folder that I created. I can not seem to get the user id. Not sure what it should be if i am using tank auth?

I use codeigniter and tank auth.

 function getAuthorName($id) {
     $ci =& get_instance();
     $ci->db->select()->from('users')->where('id', $user_id);
     $result = $ci->db->get()->result_array();
     return $result[0]['username'];
 }

 function getAuthorAvatar($id){
     $ci =& get_instance();
     $ci->db->select()->from('users')->where('id', $user_id);
     $result = $ci->db->get()->result_array();
     return $result[0]['avatar_link'];
 }

Answer 1

There is a mistake in your where-clause. try:

$ci->db->select()->from('users')->where('id', $id);