Codeigniter: CRUD (create read update and delete)

tb_crud.sql CREATE TABLE IF NOT EXISTS `tb_crud` (
     `ID_crud` int(11) NOT NULL AUTO_INCREMENT,
     `title` varchar(100) NOT NULL,
     `content` text NOT NULL,
     `modified` datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
     `slug` varchar(100) NOT NULL,
     PRIMARY KEY (`ID_crud`)
);
./application/config/autoload.php $autoload['libraries'] = array('database', 'form_validation');
$autoload['helper'] = array('url', 'html');
./application/controllers/crud.php <?php if (!defined('BASEPATH')) exit('No direct script access allowed');

class Crud extends CI_Controller {

     public function __construct() {
          parent::__construct();
     }

     public function index() {
          $validation = array(
               array('field' => 'title', 'rules' => 'required'),
               array('field' => 'content', 'rules' => 'required')
          );
          $this->form_validation->set_rules($validation);
          $this->form_validation->set_message('required', 'Tolong jangan kosong');
          if ($this->form_validation->run() == true) {
               $insert = array(
                    'title' => $this->input->post('title'),
                    'content' => $this->input->post('content'),
                    'modified' => date('Y-m-d H:i:s'),
                    'slug' => strtolower(url_title($this->input->post('title'))),
               );
               $this->db->insert('tb_crud', $insert);
               redirect('crud');
          }

          /* insert value cookie */
          $data['title'] = set_value('title');
          $data['content'] = set_value('content');
          /* end insert value cookie */

          $data['result'] = $this->db->get('tb_crud')->result();

          $this->load->view('crud', $data);
     }

     public function edit($ID_crud) {
          $validation = array(
               array('field' => 'title', 'rules' => 'required'),
               array('field' => 'content', 'rules' => 'required')
          );
          $this->form_validation->set_rules($validation);
          $this->form_validation->set_message('required', 'Tolong jangan kosong');
          if ($this->form_validation->run() == true) {
               $update = array(
                    'title' => $this->input->post('title'),
                    'content' => $this->input->post('content'),
                    'modified' => date('Y-m-d H:i:s'),
                    'slug' => strtolower(url_title($this->input->post('title'))),
               );
               $this->db->where('ID_crud', $ID_crud);
               $this->db->update('tb_crud', $update);
               redirect('crud');
          }

          // mengambil data dari database
          $this->db->where('ID_crud', $ID_crud);
          $update = $this->db->get('tb_crud')->row();

          /* update value */
          $data['title'] = $update->title;
          $data['content'] = $update->content;
          /* end update value */

          $data['result'] = $this->db->get('tb_crud')->result();

          $this->load->view('crud', $data);
     }

     function view($slug) {
          /* /crud/view/$slug : '$this->uri->segment(3)' */

          $this->db->where('slug', $slug);
          $data['detail'] = $this->db->get('tb_crud')->row();
          $this->load->view('detail_crud', $data);
     }

     function delete($ID_crud) {
          $this->db->where('ID_crud', $ID_crud);
          $this->db->delete('tb_crud');
          redirect('crud');
     }

}

/* End of file crud.php */
/* Location: ./application/controllers/crud.php */
./application/views/crud.php // html form input dan edit
<?=form_open();?>
<table style="width:100%">
     <tr>
          <td>Title</td>
          <td>
               <?=form_input(array('name' => 'title', 'class' => 'form', 'value' => $title));?>
               <?=form_error('title', '<div class="error">', '</div>'); ?>
          </td>
     </tr>
     <tr>
          <td valign="top">Content</td>
          <td>
               <?=form_textarea(array('name' => 'content', 'class' => 'form', 'value' => $content));?>
               <?=form_error('content', '<div class="error">', '</div>');?>
          <td>
     </tr>
     <tr>
          <td> </td>
          <td><?=form_submit('submit', 'Submit');?></td>
     </tr>
</table>
<?=form_close();?>
// html view result
<table cellpadding="0" cellspacing="0" border="1" style="width:100%">
     <tr>
          <th align="left" width="10%">Title</th>
          <th align="left" width="60%">Content</th>
          <th align="left">Date</th>
          <th align="left">Slug</th>
          <th align="left">Options</th>
     </tr>
     <?php
     foreach ($result as $data) {
          echo '<tr>';
          echo '<td>'.anchor('crud/view/'.$data->slug, $data->title.'</td>';
          echo '<td>'.$data->content.'</td>';
          echo '<td>'.$data->modified.'</td>';
          echo '<td>'.$data->slug.'</td>';
          echo '<td>'.anchor('crud/edit/'.$data->ID_crud, 'Edit').' | '.anchor('crud/delete/'.$data->ID_crud, 'Delete').'</td>';
          echo '</tr>';
     }
     ?>
</table>
./application/views/detail_crud.php
<table cellpadding="0" cellspacing="0" border="1" style="width:100%">
     <tr>
          <th align="left">Title</th>
          <th align="left">Content</th>
          <th align="left">Date</th>
     </tr>
     <?php
     echo '<tr>';
     echo '<td>'.$detail->title.'</td>';
     echo '<td>'.$detail->content.'</td>';
     echo '<td>'.$detail->modified.'</td>';
     echo '</tr>';
     ?>
</table>