通过Yii中的CDbCriteria选择一个表达式

Question

firstly, I using the codes below:

$c = new CDbCriteria();

$c->select = '*, DATEDIFF(deadline_time, NOW()) AS day_left';
$c->addCondition('DATEDIFF(deadline_time, NOW()) > 0');
$c->addCondition('DATEDIFF(deadline_time, NOW()) < :diff');
$c->params += array(':diff' => $diff);

$assigns = UserAssign::model()->findAll($c);

the query works fine, but I want to add some new condition through relations, so the codes turned to like this:

$c = new CDbCriteria();
$c->with = array('user');

if(Yii::app()->user->model->isAreaAdministrator) {
    $c->addCondition('user.city_id = :cityId');
    $c->params += array(':cityId' => Yii::app()->user->model->adminCityId);
}

$c->select = '*, DATEDIFF(deadline_time, NOW()) AS day_left';
$c->addCondition('DATEDIFF(deadline_time, NOW()) > 0');
$c->addCondition('DATEDIFF(deadline_time, NOW()) < :diff');
$c->params += array(':diff' => $diff);

$assigns = UserAssign::model()->findAll($c);

After I add the with property, the query seems not working, it dump the message trying to select an invalid column "DATEDIFF(deadline_time" error.

I'm newbie to Yii, could anyone help me? Thanks.

Answer 1

Replace DATEDIFF(deadline_time, NOW()) in the conditions with

new CDbExpression('DATEDIFF(deadline_time, NOW())')

I'm not sure it works in the select though. In case it doesn't you can use the afterFind function to set a public variable $day_left to the value of the DATEDIFF(deadline_time, NOW())'

class UserAssign{
    public $day_left;//new variable
    ...

    public function afterFind(){
        $this->day_left=date_diff(date_create($this->deadline_time),date_create('now'))->format('%R%a days');
        return parent::afterFind();
    }
}