Help session grab user_id from database

[eluser]the_unforgiven[/eluser]
Controller to check login then store some session data:

Code:

function check()
{
  // Check user and password
  $query = $this->user_model->checkUser();
  
  $username = $this->input->post('username');
  $password = sha1($this->input->post('password'));
  
  $this->form_validation->set_rules('username', 'required|trim|max_length[15]');
  $this->form_validation->set_rules('password', 'required|trim|sha1');
    
  if ($this->form_validation->run() === FALSE) {
  
   $data['title'] = "Customer Login";
   $this->load->view('user/logon', $data);
  }
  else {
   if($query) {
    $data = array(
                 'username'    => $this->input->post('username'),
     'is_user'     => true,
     'last_login'  => time(),
     'customer_id' => $this->user_model->getCustomer(),
     'cust_id'     => $this->session->userdata('id')
              );
    
    $this->session->set_userdata($data);
    redirect('user/myaccount');
   }
  }
}

Model to getCustomer()

Code:

function getCustomer()
{
   $data = array();

   $Q = $this->db->get('users');
   if ($Q->num_rows() > 0){
        $data = $Q->row_array();
   }
     $Q->free_result();    
     return $data;
}