AWS documentdb documentation change

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

File: documentdb/latest/developerguide/addFields.md

Summary

Added new documentation page for the $addFields aggregation pipeline stage in Amazon DocumentDB, including description, parameters, MongoDB Shell example, and code examples in Node.js and Python

Security assessment

This change adds routine documentation for a database aggregation feature ($addFields) without any security context. The content includes standard code examples for connecting to DocumentDB with TLS enabled (as shown in the connection strings with tls=true and tlsCAFile parameters), but this is standard security practice for database connections, not a response to a specific security issue. The change appears to be routine feature documentation addition.

Diff

diff --git a/documentdb/latest/developerguide/addFields.md b/documentdb/latest/developerguide/addFields.md
index 8b1378917..929f60cc8 100644
--- a//documentdb/latest/developerguide/addFields.md
+++ b//documentdb/latest/developerguide/addFields.md
@@ -0,0 +1 @@
+[](/pdfs/documentdb/latest/developerguide/developerguide.pdf#addFields "Open PDF")
@@ -1,0 +3,154 @@
+[Documentation](/index.html)[Amazon DocumentDB](/documentdb/index.html)[Developer Guide](what-is.html)
+
+Example (MongoDB Shell)Code examples
+
+# $addFields
+
+The `$addFields` stage in the Amazon DocumentDB aggregation pipeline allows you to add new computed fields to documents. This can be useful for adding derived or transformed data to the documents.
+
+**Parameters**
+
+  * `newField`: The name of the new field to add.
+
+  * `expression`: An expression that resolves to the value of the new field.
+
+
+
+
+## Example (MongoDB Shell)
+
+The following example demonstrates how to use `$addFields` to add a new field `TotalInventory` that calculates the total inventory based on the `Inventory.OnHand` and `Inventory.OrderQnty` fields.
+
+**Create sample documents**
+    
+    
+    db.example.insertMany([
+      {
+        "Item": "Spray Paint",
+        "Colors": ["Black", "Red", "Green", "Blue"],
+        "Inventory": {
+          "OnHand": 47,
+          "MinOnHand": 50,
+          "OrderQnty": 36
+        },
+        "UnitPrice": 3.99
+      },
+      {
+        "Item": "Ruler",
+        "Colors": ["Red", "Green", "Blue", "Clear", "Yellow"],
+        "Inventory": {
+          "OnHand": 47,
+          "MinOnHand": 40
+        },
+        "UnitPrice": 0.89
+      }
+    ]);
+
+**Query example**
+    
+    
+    db.example.aggregate([
+      {
+        $addFields: {
+          TotalInventory: { $add: ["$Inventory.OnHand", "$Inventory.OrderQnty"] }
+        }
+      }
+    ])
+
+**Output**
+    
+    
+    [
+      {
+        "_id" : ObjectId("5bedafbcf65ff161707de24f"),
+        "Item" : "Ruler",
+        "Colors" : [ "Red", "Green", "Blue", "Clear", "Yellow" ],
+        "Inventory" : {
+          "OnHand" : 47,
+          "MinOnHand" : 40
+        },
+        "UnitPrice" : 0.89,
+        "TotalInventory" : 47
+      },
+      {
+        "_id" : ObjectId("5bedafbcf65ff161707de250"),
+        "Item" : "Spray Paint",
+        "Colors" : [ "Black", "Red", "Green", "Blue" ],
+        "Inventory" : {
+          "OnHand" : 47,
+          "MinOnHand" : 50,
+          "OrderQnty" : 36
+        },
+        "UnitPrice" : 3.99,
+        "TotalInventory" : 83
+      }
+    ]
+
+## Code examples
+
+To view a code example for using the `$addFields` command, choose the tab for the language that you want to use:
+
+Node.js
+    
+    
+    
+    const { MongoClient } = require('mongodb');
+    
+    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('example');
+    
+    const result = await collection.aggregate([
+      {
+        $addFields: {
+          TotalInventory: { $add: ['$Inventory.OnHand', '$Inventory.OrderQnty'] }
+        }
+      }
+    ]).toArray();
+    
+    console.log(result);
+    
+    await client.close();
+
+Python
+    
+    
+    
+    from pymongo import MongoClient
+    
+    client = MongoClient('mongodb://<username>:<password>@<cluster-endpoint>:27017/?tls=true&tlsCAFile=global-bundle.pem&replicaSet=rs0&readPreference=secondaryPreferred&retryWrites=false')
+    db = client['test']
+    collection = db['example']
+    
+    result = list(collection.aggregate([
+        {
+            '$addFields': {
+                'TotalInventory': { '$add': ['$Inventory.OnHand', '$Inventory.OrderQnty'] }
+            }
+        }
+    ]))
+    
+    print(result)
+    client.close()
+
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+
+To use the Amazon Web Services Documentation, Javascript must be enabled. Please refer to your browser's Help pages for instructions.
+
+[Document Conventions](/general/latest/gr/docconventions.html)
+
+$addToSet
+
+$allElementsTrue
+
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