Thanks a lot mario, thanks once again for the good help, It work all the way I required,
Is it a good way to do the slug in this way ?
$segment = $this->uri->segment(1);
$get_link = $this->admin_user->slug($segment);
$id = $get_link[0]['link_id'];
if(intval($id) > 0) {
$this->details($id);
} else {
$this->$id();
}