Округление цен в магазине

<?php
	define('PATH', dirname(__FILE__));
	define("VALID_CMS", 1);
	include(PATH.'/core/cms.php');
    $inCore 	= cmsCore::getInstance();
    $inDB       = cmsDatabase::getInstance();
	$sql = "SELECT a.id, a.price FROM cms_shop_items a";
	$result = $inDB->query($sql);
    if(!$inDB->num_rows($result)){ return false; }
    while ($item = $inDB->fetch_assoc($result)){
            $new_price = my_ceil( $item['price']);
            echo $item['price'] .' --- '. $new_price.'<br >';
            $id=$item['id'];
            $sql = "UPDATE cms_shop_items set price = $new_price WHERE id= $id";
            $inDB->query($sql);
        }
    function my_ceil($f, $b=5) {
	    return ceil(ceil($f)/$b)*$b;
    }
?>