数据不会显示在Codeigniter中

Question

I am new learner of CI. I want to display data from database. but it doesn't work.

Code in controller :

     function __construct()
 {
   parent::__construct();
   $this->load->database();
   $this->load->model("user_model");
   $this->lang->load('basic', $this->config->item('language'));
    // redirect if not loggedin
    if(!$this->session->userdata('logged_in')){
        redirect('login');

    }
    $logged_in=$this->session->userdata('logged_in');
    if($logged_in['base_url'] != base_url()){
    $this->session->unset_userdata('logged_in');        
    redirect('login');
    }

 }

public function index($limit='0')
{


    $logged_in=$this->session->userdata('logged_in');

        if($logged_in['su']!='1'){
        exit($this->lang->line('permission_denied'));
        }


    $data['limit']=$limit;
    $data['title']=$this->lang->line('userlist');       
    // fetching user list
    $data['result']=$this->user_model->user_list($limit);

    $this->load->view('header',$data);
    $this->load->view('user_list',$data);
    $this->load->view('footer',$data);
}


    public function teachercontrol()
{
    $logged_in=$this->session->userdata('logged_in');
    $sut='2';
    $this->db->where('su',$sut);
    // fetching user list
    $data['teacher']=$this->user_model->teachermodel();     
    $this->load->view('header',$data);
    $this->load->view('user_list',$data);
    $this->load->view('footer',$data);
}

my model :

function teachermodel(){
    $this->db->order_by('savsoft_users.uid','desc');
     $this -> db -> join('savsoft_group', 'savsoft_users.gid=savsoft_group.gid');
     $query=$this->db->get('savsoft_users');
    return $query->result_array();

}

I try tro print in view, but it doesn't show any data :

<?php print_r($teacher)?>

What is the mistake? while, the index function in controller (above the teachercontroller function) works well Thanks

Answer 1

Put where condition in modal from teacher controller:

public function teachercontrol()
{
    $logged_in=$this->session->userdata('logged_in');
    $sut='2';
    // fetching user list
    $data['teacher']=$this->user_model->teachermodel($sut);     
    $this->load->view('header',$data);
    $this->load->view('user_list',$data);
    $this->load->view('footer',$data);
}

my model :

function teachermodel($sut = ""){
    if($sut != "") {
       $this->db->where('savsoft_users.su',$sut);
    }
    $this->db->join('savsoft_group', 'savsoft_users.gid=savsoft_group.gid', 'left');
    $this->db->order_by('savsoft_users.uid','desc');
    $query=$this->db->get('savsoft_users');
    return $query->result_array();
}