Read Data from MongoDB

Overview

On this page, you can see copyable code examples that show common methods you can use to retrieve documents with PyMongo.

To use an example from this page, copy the code example into the sample application or your own application. Be sure to replace all placeholders in the code examples, such as <connection string URI>, with the relevant values for your MongoDB deployment.

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import pymongo
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from pymongo import MongoClient
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try:
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    uri = "<connection string URI>"
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    client = MongoClient(uri)
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    database = client["<database name>"]
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    collection = database["<collection name>"]
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    # start example code here
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    # end example code here
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    client.close()
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except Exception as e:
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    raise Exception(
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        "The following error occurred: ", e)

Find One

results = collection.find_one({ "<field name>" : "<value>" })
print(results)

To learn more about the find_one() method, see Find One Document in the Retrieve Data guide.

Find Multiple

results = collection.find({ "<field name>" : "<value>" })
for document in results:
    print(document)

To learn more about the find() method, see Find Multiple Documents in the Retrieve Data guide.

Count Documents in a Collection

count = collection.count_documents({})
print(count)

To learn more about the count_documents() method, see the Retrieve an Accurate Count guide.

Count Documents Returned from a Query

count = collection.count_documents({ "<field name>": "<value>" })
print(count)

To learn more about the count_documents() method, see the Retrieve an Accurate Count guide.

Estimated Document Count

count = collection.estimated_document_count()
print(count)

To learn more about the estimated_document_count() method, see the Retrieve an Estimated Count guide.

Retrieve Distinct Values

results = collection.distinct("<field name>")
for document in results:
    print(document)

To learn more about the distinct() method, see the Retrieve Distinct Field Values guide.

Monitor Data Changes

with collection.watch() as stream:
    for change in stream:
        print(change)

To learn more about the watch() method, see the Monitor Data Changes guide.