How do I use pymongo to connect to an existing document collection/db?

Question

On the command line, this works:

$ mongo
> show dbs
mydatabase   1.0GB

However, this does not:

$ python    
>>> import pymongo
>>> connection = pymongo.MongoClient()
>>> connection.mydatabase.find()

I read through docs here:

http://api.mongodb.org/python/current/tutorial.html

But do not understand how to either...

1. connect to an existing database (using pymongo)
2. query what databases exist in the mongodb connection.

Why can't I access my database?

Answer 1

The question implies user has a local MongoDB. However I found this question trying to connect to a remote MongoDB. I think the tutorial is worth mentioning (no other answer here mentioned how I can specify the host and the port)

The above code will connect on the default host and port. We can also specify the host and port explicitly, as follows:

client = MongoClient('localhost', 27017)

Or use the MongoDB URI format:

client = MongoClient('mongodb://localhost:27017/')

Answer 2

Connect to an existing database

import pymongo
from pymongo import MongoClient
connection = MongoClient()
db = connection.mydatabase

List existing databases

import pymongo
from pymongo import MongoClient
connection = MongoClient()
# connection.database_names() # depreciated
connection.list_database_names()