yii计算数据库的记录条数

      $connection=Yii::app()->db;
         
         $command = $connection->createCommand("   sql语句  ");
         $dataReader = $command->query();
         $count = $dataReader->rowCount;
         $renderdoctor = array();
         foreach ($dataReader as $row) {
             
             $renderdoctor[] = $row;
             
         }
 $count = Report::model()->count();