AWS documentdb documentation change

Service: documentdb · 2026-03-31 · Documentation low

File: documentdb/latest/developerguide/dollar-update.md

Summary

Added new documentation page for the $ positional operator in Amazon DocumentDB, including parameters, MongoDB shell example, and code examples in Node.js and Python

Security assessment

This is a routine documentation addition for a MongoDB operator feature. The change documents how to use the $ positional operator for updating array elements. While the code examples include TLS connection parameters (tls=true, tlsCAFile=global-bundle.pem), this is standard secure connection practice for DocumentDB and not indicative of addressing a specific security vulnerability. No security incidents, vulnerabilities, or weaknesses are mentioned in the documentation.

Diff

diff --git a/documentdb/latest/developerguide/dollar-update.md b/documentdb/latest/developerguide/dollar-update.md
index 8b1378917..98a5a907e 100644
--- a//documentdb/latest/developerguide/dollar-update.md
+++ b//documentdb/latest/developerguide/dollar-update.md
@@ -0,0 +1 @@
+[](/pdfs/documentdb/latest/developerguide/developerguide.pdf#dollar-update "Open PDF")
@@ -1,0 +3,116 @@
+[Documentation](/index.html)[Amazon DocumentDB](/documentdb/index.html)[Developer Guide](what-is.html)
+
+Example (MongoDB Shell)Code examples
+
+# $
+
+The `$` positional operator updates the first array element that matches the query condition. It acts as a placeholder for the matched array element's position.
+
+**Parameters**
+
+  * `field.$`: The array field with the positional operator to update the first matching element.
+
+
+
+
+## Example (MongoDB Shell)
+
+The following example demonstrates using the `$` positional operator to update a specific array element.
+
+**Create sample documents**
+    
+    
+    db.inventory.insertMany([
+      { _id: 1, item: "Widget", quantities: [10, 20, 30] },
+      { _id: 2, item: "Gadget", quantities: [5, 15, 25] }
+    ]);
+
+**Query example**
+    
+    
+    db.inventory.updateOne(
+      { _id: 1, quantities: 20 },
+      { $set: { "quantities.$": 22 } }
+    );
+
+**Output**
+    
+    
+    {
+      "_id" : 1,
+      "item" : "Widget",
+      "quantities" : [ 10, 22, 30 ]
+    }
+
+## Code examples
+
+To view a code example for using the `$` positional operator, 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('inventory');
+    
+      await collection.updateOne(
+        { _id: 1, quantities: 20 },
+        { $set: { "quantities.$": 22 } }
+      );
+    
+      const updatedDocument = await collection.findOne({ _id: 1 });
+      console.log(updatedDocument);
+    
+      await 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.inventory
+    
+        collection.update_one(
+            {'_id': 1, 'quantities': 20},
+            {'$set': {'quantities.$': 22}}
+        )
+    
+        updated_document = collection.find_one({'_id': 1})
+        print(updated_document)
+    
+        client.close()
+    
+    update_document()
+
+![Warning](https://d1ge0kk1l5kms0.cloudfront.net/images/G/01/webservices/console/warning.png) **Javascript is disabled or is unavailable in your browser.**
+
+To use the Amazon Web Services Documentation, Javascript must be enabled. Please refer to your browser's Help pages for instructions.
+
+[Document Conventions](/general/latest/gr/docconventions.html)
+
+Update operators
+
+$[]
+
+Did this page help you? - Yes
+
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+
+If you've got a moment, please tell us what we did right so we can do more of it.
+
+Did this page help you? - No
+
+Thanks for letting us know this page needs work. We're sorry we let you down.
+
+If you've got a moment, please tell us how we can make the documentation better.