How to connect Python to MongoDB?¶

The pymongo library connects to a Mongo database server. It is capable of interacting with both local and remote databases. To connect to a local instance, no extra parameters are necessary.

Install it with:

pip install pymongo

Launch MongoDB through docker¶

To try MongoDB, it is best to launch it in a local docker container:

docker run -d -p 27017:27017 mongo

Run queries¶

The following code connects and runs a few queries:

import pymongo

client = pymongo.MongoClient("localhost", 27017)  # not necessary on localhost
db = client.test
print(db.name)

print(db.my_collection)
db.my_collection.insert_one({"x": 10})

db.my_collection.insert_many([
    {"pi": 3.1415},
    {"answer_to_everything": 42},
    ])
db.my_collection.insert_one({"x": 11})

# get one entry
print(db.my_collection.find_one())

# iterate over entries
for item in db.my_collection.find():
    print(item["x"])

# accelerate query with an index	
db.my_collection.create_index("x")

# sort results
for item in db.my_collection.find().sort("x", pymongo.ASCENDING):
    print(item["x"])

# chain multiple functions
print([item["x"] for item in db.my_collection.find().limit(2).skip(1)])