yanlız post'u print_r ile yazdırıp görmen lazım doğru veri gelmiş mi diye
$title = mysql_query("SELECT * FROM posts WHERE post_title");
while ($post = mysql_fetch_array($title)){
$post_title= array("id"=>$post[0]);
}
$title = mysql_query("SELECT * FROM posts WHERE post_title");
while ($post = mysql_fetch_array($title)){
$post_title= array("id"=>$post[0]);
}