Question

表结构：

餐厅：

id
title
description
etc....

折扣：

id
restaurant_id
date
percent

特殊折扣：

id
restaurant_id
from
to
percent

预订：

id
user_id
discount_id
discount_type
reserved_at

型号：

class Reservation extends Model{
    public function discount()
    {
        return $this->morphTo();
    }
}

我有两种类型的折扣：

class Discount extends Model
{
    public function reservations()
    {
        return $this->morphMany(Reservation::class, 'discount');
    }
}

和SpecialDiscount：

class SpecialDiscount extends Model
{
   public function reservations()
    {
        return $this->morphMany(Reservation::class, 'discount');
    }
}

和SpecialDiscount和Discount属于Restaurant

现在我正在尝试通过折扣访问Restaurant Reservations：

在Restaurant模型中：

  public function reservations()
  {
      $relation = $this
          ->hasManyThrough(Reservation::class, Discount::class, 'restaurant_id', 'discount_id')
          ->where('discount_type', Discount::class)->getBaseQuery();

      $relation->union($this->hasManyThrough(Reservation::class, SpecialDiscount::class, 'restaurant_id', 'discount_id')
          ->where('discount_type', SpecialDiscount::class)
          ->getBaseQuery()
          ->select('reservations.*')
      );

      return $relation;
  }

所以它出错了：

SQLSTATE [21000]：基数违反：1222使用的SELECT 语句具有不同的列数（SQL ：（从*中选择* reservations上的discounts内部联接discounts。id = reservations。discount_id，其中discounts。deleted_at为空和discount_type = App \ Models \ Discount）联合（选择 reservations。*来自reservations内部联接special_discounts special_discounts。id = reservations。discount_id其中 discount_type = App \ Models \ SpecialDiscount））

如何解决此问题？

雄辩的多态性hasManyThrough引发Cardinality违规：1222

0 个答案: