AWS documentdb documentation change

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

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

Summary

Added new documentation page for the $slice update operator in Amazon DocumentDB, including examples in MongoDB Shell, Node.js, and Python with connection strings

Security assessment

This change adds documentation for a MongoDB operator ($slice) used for array manipulation. The code examples include standard TLS connection parameters (tls=true, tlsCAFile) which are normal secure connection practices for DocumentDB, but this is not introducing new security documentation or addressing a specific security vulnerability. The change appears to be routine feature documentation.

Diff

diff --git a/documentdb/latest/developerguide/slice-update.md b/documentdb/latest/developerguide/slice-update.md
index 8b1378917..ff77fb706 100644
--- a//documentdb/latest/developerguide/slice-update.md
+++ b//documentdb/latest/developerguide/slice-update.md
@@ -0,0 +1 @@
+[](/pdfs/documentdb/latest/developerguide/developerguide.pdf#slice-update "Open PDF")
@@ -1,0 +3,142 @@
+[Documentation](/index.html)[Amazon DocumentDB](/documentdb/index.html)[Developer Guide](what-is.html)
+
+Example (MongoDB Shell)Code examples
+
+# $slice
+
+The `$slice` update operator modifies an array by limiting its size. When used with the `$push` operator, it restricts the number of elements in an array, keeping only the specified number of most recent or oldest elements.
+
+**Parameters**
+
+  * `field`: The array field to modify.
+
+  * `count`: Maximum number of elements to keep. Positive values keep the first N elements, negative values keep the last N elements.
+
+
+
+
+## Example (MongoDB Shell)
+
+The following example demonstrates how to use the `$slice` update operator with `$push` to maintain a fixed-size array of recent scores.
+
+**Create sample documents**
+    
+    
+    db.students.insertOne({
+      _id: 1,
+      name: "Alice",
+      scores: [85, 90, 78]
+    });
+
+**Query example**
+    
+    
+    db.students.updateOne(
+      { _id: 1 },
+      {
+        $push: {
+          scores: {
+            $each: [92, 88],
+            $slice: -3
+          }
+        }
+      }
+    )
+
+**Output**
+    
+    
+    {
+      "_id" : 1,
+      "name" : "Alice",
+      "scores" : [ 78, 92, 88 ]
+    }
+
+In this example, the `$slice: -3` modifier keeps only the last three elements after pushing new values to the array.
+
+## Code examples
+
+To view a code example for using the `$slice` update 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('students');
+    
+      await collection.updateOne(
+        { _id: 1 },
+        {
+          $push: {
+            scores: {
+              $each: [92, 88],
+              $slice: -3
+            }
+          }
+        }
+      );
+    
+      const updatedDocument = await collection.findOne({ _id: 1 });
+      console.log(updatedDocument);
+    
+      await client.close();
+    }
+    
+    updateDocument();
+
+Python
+    
+    
+    
+    from pymongo import MongoClient
+    
+    def update_document():
+        client = MongoClient('mongodb://<username>:<password>@<cluster-endpoint>:27017/?tls=true&tlsCAFile=global-bundle.pem&replicaSet=rs0&readPreference=secondaryPreferred&retryWrites=false')
+        db = client.test
+        collection = db.students
+    
+        collection.update_one(
+            {'_id': 1},
+            {
+                '$push': {
+                    'scores': {
+                        '$each': [92, 88],
+                        '$slice': -3
+                    }
+                }
+            }
+        )
+    
+        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)
+
+$setOnInsert
+
+$sort
+
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+
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+
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+
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