I need some help with this code

I have this code and i want to change it to get random from database.
Any ideea?

$resim = mysql_query("SELECT * FROM ".$table_prefix."postmeta LEFT OUTER JOIN ".$table_prefix."posts ON ".$table_prefix."postmeta.post_id = ".$table_prefix."posts.id Where ".$table_prefix."postmeta.meta_key='featured' ORDER By ".$table_prefix."postmeta.post_id DESC Limit 4");
for ($j=0; $niphell=mysql_fetch_array($resim); $j++){
$ust .= '<li class="ui-tabs-nav-item" id="nav-fragment-'.($j+1).'"><a href="#fragment-'.($j+1).'"><img src="'.$niphell[meta_value].'" width="120" height="90" alt="" /></a></li>
';
$alt .='<div id="fragment-'.($j+1).'" class="ui-tabs-panel" style="">
'.get_post_meta($niphell[post_id], 'embed', true).'
</div>
';
}

Hey,

Here is the only way to generate a random (anything) from an SQL database. All other ways would require additional PHP functionality

mysql_query("SELECT * FROM ".$table_prefix."postmeta LEFT OUTER JOIN ".$table_prefix."posts ON ".$table_prefix."postmeta.post_id = ".$table_prefix."posts.id WHERE ".$table_prefix."postmeta.meta_key='featured' ORDER BY RAND() LIMIT 4");

Thank you verry much, it was helpful, i chaged the old code with this one and woks great