Concat in Codeigniter Active Record
$this->db->select('user_id, user_telephone, user_email, CONCAT(user_firstname, '.', user_surname) AS name', FALSE);$this->db->from('users');$this->db->where('name', $term);Not sure why you are running multiple selects. So just put it as a single select. It's probably that the 2nd one is overriding the first one and thus overwriting the concatenation to create the name column.
$this->db->select("CONCAT((first_name),(' '),(middle_name),(' '),(last_name)) as candidate_full_name");Try like above 100% it will work in ci.
If cryptic solution doen't work then try it.
$query = "SELECT * FROM ( SELECT user_id, user_telephone, user_email, CONCAT(user_firstname, ' ', user_surname) name FROM users ) aWHERE name LIKE '%".$term."%'";$this->db->query($query);