relations报错 Trying to get property of non-object [ 新手入门 ]

public function actionIndex(){
    $model = Member::model()->with('country')->findAll();
    foreach ($model as $v){
        echo $v->country->name;
    }
}

echo $v->country->name; 就会报错， var_dump($v->country->name); 可以打印出结果

原因：数据库数据有错误