query builder

$db = \Db::getInstance();
// query returns statement
$stmt = $db->createCommand()->select()->from(array('m' => 'managers'))
->where('man_id = :man_id')->query(array('man_id' => 1));
var_dump($db->fetch_assoc($stmt));

$db = \DbFactory::getConnection('crm_extended');

// here we build select object
$select = $db->createCommand()->select()->from('error_log')->limit(1);
// we can print it anytime
echo $select;
var_dump($db->q_assoc_one($select));