where('goods_sku_id',$sku_id); if($goods_id){ $query->where('goods_id',$goods_id); } } public function install(){ return $this->belongsTo(GoodsInstall::class); } public static function getFee($sku_id,$num){ $installLink=self::where('goods_sku_id',$sku_id)->with(['install'])->find(); $fee=0; if($installLink){ $install=$installLink->install; $fee=$install->getFee($num); } return $fee; } }