有个功能，经常要根据工厂id查询数据，请问下面哪种设计比较合理？
还是说，效率都一样？

方案1：
{

     {
        "_id" : 1, 
        "product" : "产品1", 
        "price" : 5.5, 
        "quantity" : NumberInt(5), 
        "factory":"工厂1"        
    },
    {
        "_id" : 2, 
        "product" : "产品2", 
        "price" : 5.5, 
        "quantity" : NumberInt(5), 
        "factory":"工厂1"        
    },
    .....
    .....

}

方案2：
{

  "factory":"工厂1",
  "list":[
     {
        "_id" : 1, 
        "product" : "产品1", 
        "price" : 5.5, 
        "quantity" : NumberInt(5),        
    },
    {
        "_id" : 2, 
        "product" : "产品2", 
        "price" : 5.5, 
        "quantity" : NumberInt(5),        
    },

    ....
    ....

  ]

}