php - Updating with codeigniter -

i finished tutorial making news application on codeigniter user_guide. trying extend tutorial website loads text textarea can retyped , used update entry. want view article page same page updating. view loads correctly, when click submit, brings me localhost/ci/news/foo localhost/ci/news/view along 404. have tried imitate create, , altering model query, since i've been struggling while, have tried several ideas.

i suspect problem 1 of following.

something directing me ci/news/view misusing $slug variable misconnecting controller , model syntax in model query.

i'll post relevent code.

here's controller function view, updates happen.

public function view($slug) {     $this->load->helper('form');     $this->load->library('form_validation');      $data['news_item'] = $this->news_model->get_news($slug);      $slug = $slug;      $this->form_validation->set_rules('text', 'text', 'required');      if (empty($data['news_item']))     {         show_404();     }      $data['title'] = $data['news_item']['title'];     if ($this->form_validation->run() === false)     {     $this->load->view('templates/header', $data);     $this->load->view('news/view', $data);     $this->load->view('templates/footer');     }     else     {         $this->news_model->update_news();         $this->load->view('news/success');     } } 

here's update_news() in model

public function update_news($slug) { $data = array(     'slug' => $slug,     'text' => $this->input->post('text') ); $this->db->set('slug', $slug); $this->db->update('news', $data); } 

and view.php

<?php  echo validation_errors();  echo form_open('news/view');   echo '<h2>'.$news_item['title'].'</h2>'; ?>  <label for="text">text</label> <textarea name="text"><?php echo $news_item['text']; ?></textarea><br />  <input type="submit" name="submit" value="update" /> </form> 

update: requested, get_news model function.

public function get_news($slug = false) { if ($slug === false) {     $query = $this->db->get('news');     return $query->result_array(); }  $query = $this->db->get_where('news', array('slug' => $slug)); return $query->row_array(); } 

in model put instead of set.

 public function update_news($slug) { $data = array(     'slug' => $slug,     'text' => $this->input->post('text') ); $this->db->where('slug', $slug); $this->db->update('news', $data); }