Fetch node of certain type from DB via db_select
$nids = db_select('node', 'n')
->fields('n', array('nid'))
->fields('n', array('type'))
->condition('n.type', 'blog')
->execute()
->fetchCol(); // returns an indexed array
// Now return the node objects.
$nodes = node_load_multiple($nids);
//print dpm($nodes);
$rnodes = array_reverse($nodes);