Nieko sql užklausa neiš fetch php kodas nors adminerio viskas gerai atvaizduoje rezultata

Kodėl man šitas query nieko negražina kai bandau naudoti php kode o kai įrašau į adminer gražina rezultatą?

SELECT b3.setting AS setting FROM wb_seo as b1 INNER JOIN wb_seo AS b2 ON (b1.id = b2.seo_id AND b1.name= 'lt') INNER JOIN wb_seo AS b3 ON (b2.id = b3.seo_id AND b2.name= 'Kontaktai') WHERE b3.name = 'apie' LIMIT 1

duomenų bazes lentele:

http://c2n.me/iBnjoG.png

O php kodą kokį naudoji?

<?php

class db {

private $db;

public function __construct(){
	$this->db = new mysqli('localhost', 'root', 'root', 'tvs');
}

public function q ($query){
	return $this->db->query ($query);
}

public function __destruct() {
	$this->db->close ();
}
}

?>

<?php
include ("sys/db.php");

$db = new db();
$u = explode ("/",$_GET['u']);
$uu = array_filter($u, 'strlen');
$i =1;
$l = count ($uu);
$sql = "";
foreach ($uu as $v){
if ($i < $l){
	$j = $i + 1;
	$sql .= " INNER JOIN wb_seo AS b$j ON (b$i.id = b$j.seo_id AND b$i.name= '$v')\n";
	$i++;
}elseif ($i == $l){
	$sql .= " WHERE b$i.name = '$v'";
}
}
$sql = "SELECT b$i.name AS name FROM wb_seo as b1 $sql LIMIT 1\n";

$r = $db->q($sql );
$row = $r->fetch();

?>