如何禁止CActiveDataProvider进行查询？
我想根据root条件进行，如果评论不存在根，则listview不显示数据
if($rootAr==null)
{
$dataProvider=new CActiveDataProvider//？？？这里如何禁止查询和显示？
}
else
{
$commentCriteria=new CDbCriteria(array(........ ));
$dataProvider=new CActiveDataProvider(‘Topic’, array(
‘pagination’=>array(
‘pageSize’=>10,
),
‘criteria’=>$commentCriteria,
));
}
$this->render(‘view’,array(
'dataProvider'=>$dataProvider,
));