Ошибка в коде: "mysql_fetch_array() expects parameter 1 to be resource, boolean given"

<?
    function db_connect()
   
   {
    $host = 'localhost';
    $user = 'shop_user_admin';
    $password = 'admin';
    $db ='shop';
    
    $connection = mysql_connect($host, $user, $password);
    
    if (!$connection || !mysql_select_db($db,$connection))
    
    {
        return false;
    }
        return $connection;
    }
   
 
   function db_result_to_array($result)
   {
    
    $res_array = array();
    
    $count = 0;
    
    while($row = mysql_fetch_array($result))
  { 
    $res_array[$count] = $row;
    $count++;
}
   return $res_array; 
}
   function get_products()
{ 
  db_connect();
  
  $query = "SELECT * FROM products ORDER BY id DESC";
  
  $result = mysql_query($query);
  
  $result = db_result_to_array($result);
  
  return $result;
  
 }
 
 function get_cat_products($cat)
{ 
  db_connect();
  
  $query = "SELECT * FROM products WHERE cat ='$cat' ORDER BY id DESC";
  
  $result = mysql_query($query);
  
  $result = db_result_to_array($result);
  
  return $result;
  
 }
function get_cat()
{ 
  db_connect();
  
  $query = "SELECT * FROM categories ORDER BY id DESC";
  
  $result = mysql_query($query);
  
  $result = db_result_to_array($result);
  
  return $result;
  
 }
 
 function get_product($id)
 {
    db_connect();
    
    $query = ("SELECT * FROM products WHERE id='$id' ");
    
    $result = mysql_query($query);
    
    $row = mysql_fetch_array($result);
    
    return $row;
 }
 
?>[/PHP]
[PHP]<?php
$cat = $_GET['id'];
$products = get_cat_products($cat);
foreach($products as $item):
?>
 
 
 
 
 <table align="center" cellpadding="0" cellspacing="0" class="product" border="0">
            <tr>
                <td valign="top">
                  <div><a href="index.php?view=product&id=<?=$item['id']?>"><img src="userfiles/<?=$item['image']?>"alt="" /></a></div>
                    <div class="description"
                        <div class="product-name"><a href="#"><?=$item['tittle']?></a></div>
                        <div class="product-price"><?=$item['price']?></div>
                    </div>
                </td>
            </tr>
    </table>
   
<?php endforeach;?>