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();