使用Pymongo查询嵌套的JSON数据

Question

我的MongoDB文档看起来像这样（为清晰起见，删除了不重要的数据）：

{
  "posts": [
    {
      "id": 1234,
      "comments": "I want this data!"
    },
    {
      "id": 4444,
      "comments" "foo"
    }
  ]
}

只知道它在id = 1234的对象中，如何使用Pymongo（Python 3）返回“注释”值，即“我想要这个数据！”？

由于

Answer 1

遍历dicts列表，找到id == 1234然后获取comment值的词组：

 dic={
  "posts": [
    {
      "id": 1234,
      "comments": "I want this data!",
    },
    {
      "id": 4444,
      "comments": "foo",
    },
  ],
}
for d in dic["posts"]:
    if d.get("id") == 1234:
        print (d.get("comments"))
I want this data!

列表comp：

dic={
  "posts": [
    {
      "id": 1234,
      "comments": "I want this data!",
    },
    {
      "id": 4444,
      "comments": "foo",
    },
     {
      "id": 1234,
      "comments": "I want this data too!",
    },
  ],
}
print ([d.get("comments") for d in dic["posts"] if d.get("id") == 1234])
['I want this data!', 'I want this data too!']