Select average from database codeigniter - php

Question

I am trying to select average from several column from my database in using codeigniter. But I only manage to show out the average of last column from my database. What is the problem here?
View
<!--$noise is the field form database!-->
<div id = "conclusion">
<fieldset>
<h1>Tourism Rating</h1><br>
<table cellpadding = "0" cellspacing="0" border="0"><div id = "rating">
<?php foreach ($post as $row): ?>
<tr>
<td>Overall Rating</td>
<td>:</td>
<td><?php echo $row->rating;?></td>
</tr>
<?php endforeach; ?>
<?php foreach ($post as $row): ?>
<tr>
<td>% Annoying Noise</td>
<td>:</td>
<td><?php echo $row->noise;?></td>
</tr>
<?php endforeach; ?>
<?php foreach ($post as $row): ?>
<tr>
<td>Air Quality</td>
<td>:</td>
<td><?php echo $row->air;?></td>
</tr>
<?php endforeach; ?>
<?php foreach ($post as $row): ?>
<tr>
<td>Water Quality</td>
<td>:</td>
<td><?php echo $row->water;?></td>
</tr>
<?php endforeach; ?>
<?php foreach ($post as $row): ?>
<tr>
<td>Facilities</td>
<td>:</td>
<td><?php echo $row->facility;?></td>
</tr>
<?php endforeach; ?>
<?php foreach ($post as $row): ?>
<tr>
<td>Friendliness</td>
<td>:</td>
<td><?php echo $row->friend;?></td>
</tr>
<?php endforeach; ?>
</table>
</fieldset>
</div>
Controller
<?php
class viewreview extends CI_Controller {
public function view($page = 'viewreview') //writereview page folder name
{
$this->load->model('viewreview_model');
$data['query'] = $this->viewreview_model->get_data();
$this->load->vars($data);
$data['post'] = $this->viewreview_model->tourismrating();
$this->load->vars($data);
$data['post'] = $this->viewreview_model->tourismnoise();
$this->load->vars($data);
$data['post'] = $this->viewreview_model->tourismair();
$this->load->vars($data);
$data['post'] = $this->viewreview_model->tourismwater();
$this->load->vars($data);
$data['post'] = $this->viewreview_model->tourismfacility();
$this->load->vars($data);
$data['post'] = $this->viewreview_model->tourismfriend();
$this->load->vars($data);
if ( ! file_exists('application/views/viewreview/'.$page.'.php')) //link
{
// Whoops, we don't have a page for that!
show_404();
}
$data['title'] = 'View Review';
//$data['title'] = ucfirst($page); // Capitalize the first letter
$this->load->helper('html');
$this->load->helper('url');
$this->load->helper('form');
$this->load->view('templates/header', $data);
$this->load->view('viewreview/'.$page, $data);
$this->load->view('templates/footer', $data);
}
}
?>
Model
<?php
class viewreview_model extends CI_Model {
public function __construct()
{
$this->load->database();
}
public function get_data()
{
$match = $this->input->post('search');
$this->db->like('sitename',$match);
$this->db->or_like('titlereview',$match);
$this->db->or_like('yourreview',$match);
$this->db->or_like('suggestion',$match);
$query = $this->db->get('tourism'); //pass data to query
return $query->result();
}
public function tourismrating()
{
$match = $this->input->post('search');
$this->db->select('*');
$this->db->from('tourism');
$this->db->select_avg('rating');
$this->db->where('sitename', $match);
$post = $this->db->get();
return $post->result();
}
public function tourismnoise()
{
$match = $this->input->post('search');
$this->db->select('*');
$this->db->from('tourism');
$this->db->select_avg('noise');
$this->db->where('noise', $match);
$post = $this->db->get();
return $post->result();
}
public function tourismair()
{
$match = $this->input->post('search');
$this->db->select('*');
$this->db->from('tourism');
$this->db->select_avg('air');
$this->db->where('sitename', $match);
$post = $this->db->get();
return $post->result();
}
public function tourismwater()
{
$match = $this->input->post('search');
$this->db->select('*');
$this->db->from('tourism');
$this->db->select_avg('water');
$this->db->where('sitename', $match);
$post = $this->db->get();
return $post->result();
}
public function tourismfacility()
{
$match = $this->input->post('search');
$this->db->select('*');
$this->db->from('tourism');
$this->db->select_avg('facility');
$this->db->where('sitename', $match);
$post = $this->db->get();
return $post->result();
}
public function tourismfriend()
{
$match = $this->input->post('search');
$this->db->select('*');
$this->db->from('tourism');
$this->db->select_avg('friend');
$this->db->where('sitename', $match);
$post = $this->db->get();
return $post->result();
}
}
?>