title: Edit form echoes previously saved data correctly but does not update the form fields
body: <p>Echoing previously saved data (excluding those from dropdown values) already works fine for me. I could see correct data saved for a particular record, however, after editing the form, I don't see anything successful after it. The data which were supposedly edited remain the same. Everything I typed to actually edit the echoed values went nowhere.</p>
  
  <p>I currently have this in my controller:</p>
  
  <pre><code>    public function edit_job() 
  {
      $this-&gt;validateRole('client');
      $this-&gt;load-&gt;model('job_model');
  
      $id = $this-&gt;uri-&gt;segment(3,0);
  
      $data['my_preference'] = $this-&gt;array_to_select( $this-&gt;job_model-&gt;get_all_categories(), 'id','name');
      $data['job'] = $this-&gt;job_model-&gt;get_job($id);
      $this-&gt;load-&gt;view('client/edit_job', $data);
  }   
  
  public function edit_job_submit() 
  {
      $this-&gt;validateRole('client');
      $this-&gt;load-&gt;model('job_model');
  
      if ( '0' != $_POST['id'] ) 
      {
          $this-&gt;job_model-&gt;edit_job($_POST);
      } else {
          $this-&gt;job_model-&gt;add_job($_POST);
      }
      redirect('client/manage_jobs?message=Job updated.');
  }
  </code></pre>
  
  <p>While I have this in my model:</p>
  
  <pre><code>public function edit_job($obj)
  {
      $data = array
      (
          'title' =&gt; $post_obj['title'],
          'description' =&gt; $post_obj['description'],
          'start_date' =&gt; date("Y-m-d", strtotime($post_obj['start_date'])),
          'category_id' =&gt; $post_obj['category_id']
      );
      $this-&gt;db-&gt;where('id', $id);
      $this-&gt;db-&gt;update('job', $data);    
  }
  </code></pre>