Yii 实现数据库SUM操作

$criteria = new CDbCriteria();
$criteria->select = 'sum(amount) total';
$criteria->order = ‘wom_id desc’;
$criteria->addCondition(“wom_id=4");//也可以$criteria->condition = "$wom_id=4";
$aResult = Member::model()->findAll($criteria);

//获取账户已到帐总额
public static function GetAmountAlreadyArrive($int_wom_id){
$connection = Yii::app()->weimob_payment;
$str_sql  = "select sum(`ww_amount`) as `total_balance` from `t_wm_weimobpay_withdrawal_new`";
$str_sql .= " where wom_id={$int_wom_id} and ww_pay_status=1 and ww_check_status=1";
$command = $connection->createCommand($str_sql);
return $command->queryAll();
}

//获取账户提现总额
public static function getCashamount($int_wom_id){
$connection = Yii::app()->weimob_payment;
$str_sql  = "select sum(`ww_amount`) as `total_balance` from `t_wm_weimobpay_withdrawal_new`";
$str_sql .= " where wom_id={$int_wom_id} and ww_check_status!=2";
$command = $connection->createCommand($str_sql);
return $command->queryAll();
}