db_select

$query = db_select('node', 'n');
$query->fields('n', array('nid, title'));
$u_alias = $query->innerJoin('users' ,'u', '%alias.uid = n.uid');
$query->addField($u_alias, 'name', 'username');
$query->condition("{$u_alias}.name", 'Bob');
$query->condition('n.created', REQUEST_TIME - 604800, '>=');
$query->orderBy('n.created', 'DESC');
$query->range(0, 5);
$query->addTag('node_access');
$result = $query->execute();