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AWS documentdb documentation change

Service: documentdb · 2026-03-28 · Documentation low

File: documentdb/latest/developerguide/reduce.md

Summary

Entire documentation page for the $reduce aggregation operator has been removed, including all examples and explanations

Security assessment

The change removes general documentation about a database aggregation operator ($reduce) and its usage examples. There is no evidence of security vulnerability fixes, security patches, or security-related content in the removed material. The removal appears to be a routine documentation cleanup or restructuring without any security implications mentioned in the diff.

Diff

diff --git a/documentdb/latest/developerguide/reduce.md b/documentdb/latest/developerguide/reduce.md
index 8522ea0db..8b1378917 100644
--- a//documentdb/latest/developerguide/reduce.md
+++ b//documentdb/latest/developerguide/reduce.md
@@ -1 +0,0 @@
-[](/pdfs/documentdb/latest/developerguide/developerguide.pdf#reduce "Open PDF")
@@ -3,153 +1,0 @@
-[Documentation](/index.html)[Amazon DocumentDB](/documentdb/index.html)[Developer Guide](what-is.html)
-
-Example (MongoDB Shell)Code examples
-
-# $reduce
-
-The `$reduce` aggregation operator in Amazon DocumentDB is used to apply a function of two arguments cumulatively to the elements of an array to reduce the array to a single value. This operator is particularly useful for performing complex calculations or transformations on array data within the aggregation pipeline.
-
-**Parameters**
-
-  * `input`: The array to be reduced.
-
-  * `initialValue`: The initial value to be used in the reduction operation.
-
-  * `in`: The expression to be evaluated on each element of the `input` array. This expression should return a value that will be used in the next iteration of the reduction.
-
-
-
-
-## Example (MongoDB Shell)
-
-The following example demonstrates how to use the `$reduce` operator to calculate the sum of all elements in an array.
-
-**Create sample documents**
-    
-    
-    db.orders.insertMany([
-      { "_id": 1, "items": [1, 2, 3, 4, 5] },
-      { "_id": 2, "items": [10, 20, 30] },
-      { "_id": 3, "items": [5, 15, 25, 35] },
-      { "_id": 4, "items": [100, 200] }
-    ])
-
-**Query example**
-    
-    
-    db.orders.aggregate([
-      {
-        $project: {
-          total: {
-            $reduce: {
-              input: "$items",
-              initialValue: 0,
-              in: { $add: ["$$value", "$$this"] }
-            }
-          }
-        }
-      }
-    ])
-
-**Output**
-    
-    
-    [
-      { "_id": 1, "total": 15 },
-      { "_id": 2, "total": 60 },
-      { "_id": 3, "total": 80 },
-      { "_id": 4, "total": 300 }
-    ]
-
-The `$reduce` operator iterates over the `items` array, adding each element to the `initialValue` of 0. The result is the sum of all elements in the array.
-
-## Code examples
-
-To view a code example for using the `$reduce` command, choose the tab for the language that you want to use:
-
-Node.js
-    
-
-Here's an example of using the `$reduce` operator in a Node.js application:
-    
-    
-    const { MongoClient } = require("mongodb");
-    
-    async function main() {
-      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 orders = db.collection("orders");
-    
-      const result = await orders.aggregate([
-        {
-          $project: {
-            total: {
-              $reduce: {
-                input: "$items",
-                initialValue: 0,
-                in: { $add: ["$$value", "$$this"] }
-              }
-            }
-          }
-        }
-      ]).toArray();
-    
-      console.log(result);
-      await client.close();
-    }
-    
-    main();
-
-Python
-    
-
-Here's an example of using the `$reduce` operator in a python application:
-    
-    
-    from pymongo import MongoClient
-    
-    def main():
-        client = MongoClient("mongodb://<username>:<password>@<cluster-endpoint>:27017/?tls=true&tlsCAFile=global-bundle.pem&replicaSet=rs0&readPreference=secondaryPreferred&retryWrites=false")
-        db = client["test"]
-        orders = db["orders"]
-    
-        result = list(orders.aggregate([
-            {
-                "$project": {
-                    "total": {
-                        "$reduce": {
-                            "input": "$items",
-                            "initialValue": 0,
-                            "in": { "$add": ["$$value", "$$this"] }
-                        }
-                    }
-                }
-            }
-        ]))
-    
-        print(result)
-        client.close()
-    
-    if __name__ == "__main__":
-        main()
-
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-
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-
-[Document Conventions](/general/latest/gr/docconventions.html)
-
-$redact
-
-$regexFind
-
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