gorm.Model
	Name  string
	Code  string
	Price int64
	Owner string
	Item  ProductItem
}

type ProductItem struct {
	gorm.Model
	Code               string
	Product4ID         uint
	AfterFindCallTimes int
}

func (pi ProductItem) BeforeCreate(*gorm.DB) error {
	if pi.Code == "invalid" {
		return errors.New("invalid item")
	}
	return nil
}