pymongo 获取所有集合的键

Question

我需要一个代码来显示所有集合名称的主键。我希望能够在不同的 mongo 实例上使用它，所以我不想使用集合的确切名称。

import pymongo
import sys
import json

    from pymongo import MongoClient
    
    
        if __name__ == '__main__':
            client = pymongo.MongoClient("localhost", 27017, maxPoolSize=50)
            db = client.list_database_names()
            document = db.collection_name.find_one()
            for k in document:
                print(k)

但是当我运行它时，它输出

Traceback (most recent call last):
  File "bla.py", line 12, in <module>
    document = db.collection_name.find_one()
AttributeError: 'list' object has no attribute 'collection_name'

这里有什么问题？

Answer 1

db 是所有数据库名称的列表您必须为每个数据库名称获取一个数据库对象。然后你必须得到每个数据库的所有集合。您将能够打印每个集合的第一个文档

import pymongo
import sys
import json

from pymongo import MongoClient

if __name__ == '__main__':
    client = pymongo.MongoClient("localhost", 27017, maxPoolSize=50)
    list_databases = client.list_database_names()

    for database_name in list_databases:
        # Create a Database object
        db = client.get_database(database_name)
        
        # Get list of collections names in that database
        list_collections = db.collection_names()

        for collection_name in list_collections:
            # Create a colection object
            collection = db.get_collection(collection_name)

            # Print the first element of that collection
            print(collection.find_one())

pymongo 获取所有集合的键

pymongo get keys of all collections

python

mongodb

pymongo