strange mysql and php behavior -

this strange question use query value database based on name name exist in database , if add new product grabs name on old products not

here db structure vaporama.be sql pdf

site demo http://vaporama.be

pphp code

try {     $stmt = $db->prepare("select * category cat = 'product' order name asc");     $stmt->execute();     $category = $stmt->fetchall(pdo::fetch_assoc);     foreach($category $cat) {         $naam = $cat['name'];         //subcats query en count         $stmt2 = $db->prepare("select * products cat = :name group (merk) order name asc");         $stmt2->execute(array(':name' => $naam));         $count = $stmt2->rowcount();         //echo cats         echo "                 <li class='dropdown'>                     <a class='dropdown-toggle' href='#'>                         {$naam} ({$count})                     </a>             ";         $subcat = $stmt2->fetchall(pdo::fetch_assoc);         //echo subcats         echo "<ul class='dropdown-menu'>";         foreach($subcat $sub) {             $stmt3 = $db->prepare("select * merken name = :merk order name asc");             $stmt3->execute(array(':merk' => $sub['merk']));             $merk = $stmt3->fetch(pdo::fetch_assoc);             echo "                     <li><a href='//{$_server['server_name']}/merk?merk={$merk[id]}'>{$sub[merk]}</a></li>                 ";         }         echo "</ul>";     } } catch(exception $e) {     echo '<h2><font color=red>';     var_dump($e->getmessage());     die ('</h2></font> '); } 

so basicly should show , grab id not does

but if add new product , work more fun , code says group names should unic in dropdown see 2 time joyetech first 1 not contain id , second contains id ( 33 )

so why not group result , doesnt find need ? here db of working item ( id 33 ) , above non working item

id | name | merk
64 | test | joyetech

i not see difference ? greets powerchaos

and here screenshot how looks