Update Document In Collection

In MongoDB, To update a row (document) in MongoDB using Python, we typically use the "update_one()" or "update_many()" method provided by the `pymongo` library.

Here's an example of how you can update a row in MongoDB using "PyMongo":

Document Update Syntax:

Syntax:

# Define the update operation
update = {"$set": {"field_to_update": "new_value"}}

MongoDB Configuration:

After importing "pymongo", we must provide a connection URL and database name to MongoClient.

Example:

# import pymongo library
import pymongo

# Connect to MongoDB
client = pymongo.MongoClient("mongodb://localhost:27017/")

db = client["your_database_name"]
collection = db["your_collection_name"]

Make sure to replace "your_database_name" and "your_collection_name" with your actual database, and collection name respectively.

Update Specific Document In Collection

Example:

# Define the filter to find the document to update
filter = {"_id": ObjectId("document_id_to_update")}

# Update a single document that matches the filter
result = collection.update_one(filter, update)

# Print information about the update

# It will display no. of Document matched above query.
print("Matched:", result.matched_count) 

# it will display actual no. of Document updated/affected.
print("Modified:", result.modified_count)

"filter" specifies the criteria for finding the document we want to update. Replace "document_id_to_update" with the actual "ID" of the document we want to update.
"update" specifies the modification we want to make. In this case, we use "$set" to update specific fields.
"update_one()" is used to update a single document that matches the filter. If we want to update multiple documents, we can use "update_many()" instead.
"result.matched_count" returns the number of documents that matched the filter, and "result.modified_count" returns the number of documents that were modified.
Make sure to replace "document_id_to_update", and "field_to_update" with your actual database, and collection name respectively.

Update Many Documents in Collection:

Using the "filter" object, we can find all documents that matched the criteria and were eligible for the update.

With the help of "$set: { any_key_data_to_be_update }" we can modify our existing documents in the collection.

Example:

# Define the filter to find the documents to update
filter = {age: {$gt: 18}} # will update all document whose age is greater than 18

# Define the update operation
update = {"$set": {"isEligible": true}}

# Update a single document that matches the filter
result = collection.update_many(filter, update)

# Print information about the update

# It will display no. of Documents matched above query.
print("Matched:", result.matched_count) 

# it will display actual no. of Document updated/affected.
print("Modified:", result.modified_count)

Note: "update_many()" updates all documents that match the filter with the specified update.

<-- Insert Document

Find Document -->