$push - Amazon DocumentDB
Example (MongoDB Shell)Code examples

$push

The $push operator in Amazon DocumentDB is used to add an item to an array field in a document. This operator is particularly useful when you need to append new data to an existing array without overwriting the entire array.

Parameters

  • field: The name of the array field to which the new element should be added.

  • value: The value to be added to the array.

  • position: (optional) A modifier that specifies the position in the array where the new element should be added. Supported modifiers include $ (add to the end of the array) and $[] (add to the end of the array, ignoring any array filters).

Example (MongoDB Shell)

The following example demonstrates how to use the $push operator to add new elements to an array field in a document.

Create sample documents

db.users.insert([
  { _id: 1, name: "John Doe", hobbies: ["reading", "swimming"] },
  { _id: 2, name: "Jane Smith", hobbies: ["gardening", "cooking"] }
])

Query example

db.users.updateOne(
  { _id: 1 },
  { $push: { hobbies: "hiking" } }
)

Output

{
  "acknowledged" : true,
  "matchedCount" : 1,
  "modifiedCount" : 1
}

After running the update, the document with _id: 1 will have the hobbies array updated to ["reading", "swimming", "hiking"].

Code examples

To view a code example for using the $push command, choose the tab for the language that you want to use:

Node.js
const { MongoClient } = require('mongodb');

async function updateDocument() {
  const client = await MongoClient.connect('mongodb://<username>:<password>@<cluster-endpoint>:27017/?tls=true&tlsCAFile=global-bundle.pem&replicaSet=rs0&readPreference=secondaryPreferred&retryWrites=false');
  const db = client.db('test');
  const collection = db.collection('users');

  const result = await collection.updateOne(
    { _id: 1 },
    { $push: { hobbies: "hiking" } }
  );

  console.log(result);
  client.close();
}

updateDocument();
Python
from pymongo import MongoClient

def update_document():
    client = MongoClient('mongodb://<username>:<password>@<cluster-endpoint>:27017/?tls=true&tlsCAFile=global-bundle.pem&replicaSet=rs0&readPreference=secondaryPreferred&retryWrites=false')
    db = client['test']
    collection = db['users']

    result = collection.update_one(
        {'_id': 1},
        {'$push': {'hobbies': 'hiking'}}
    )

    print(result.raw_result)
    client.close()

update_document()