belongsTo('App\Users', 'user_id', 'id')->value('phone'); if(empty($res)){ $res=$this->belongsTo('App\Users', 'user_id', 'id')->value('email'); } return $res; } public function getTouchMobileAttribute() { $res=$this->belongsTo('App\Users', 'touch_user_id', 'id')->value('phone'); if(empty($res)){ $res=$this->belongsTo('App\Users', 'touch_user_id', 'id')->value('email'); } return $res; } }