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

New from version 4.0.

Not supported by Elastic cluster.

The $rtrim operator in Amazon DocumentDB is used to remove trailing characters from a string. By default, it removes trailing whitespace characters, but you can also specify a set of characters to remove by passing the chars argument.

Parameters

  • input: The input string from which to remove trailing whitespace characters.

  • chars: (optional) To remove specific characters.

Example (MongoDB Shell)

The following example demonstrates how to use the $rtrim operator to remove trailing specified characters (" *") from a string.

Create sample documents

db.collection.insert([
  { "name": "John Doe*  ", "age": 30 },
  { "name": "Jane Smith  ", "age": 25 },
  { "name": "Bob Johnson", "age": 35 }
]);

Query example

db.collection.aggregate([
  {
    $project: {
      _id: 0,
      name: { $rtrim: { input: "$name", chars: " *" } }, 
      age: 1
    }
  }
]);

Output

[
  { age: 30, name: 'John Doe' },
  { age: 25, name: 'Jane Smith' },
  { age: 35, name: 'Bob Johnson' }
]

Code examples

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

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

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

  try {

    const db = client.db('test');
    const collection = db.collection('collection');  

    const pipeline = [
      {
        $project: {
          _id: 0,
          name: { $rtrim: { input: "$name", chars: " *" } },
          age: 1
        }
      }
    ];

    const results = await collection.aggregate(pipeline).toArray();
    console.dir(results, { depth: null });

  } catch (err) {
    console.error('Error occurred:', err);
  } finally {
    await client.close();
  }
}

example().catch(console.error);
Python
from pymongo import MongoClient

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

    try:

        db = client.test
        collection = db.collection

        pipeline = [
            {
                "$project": {
                    "_id": 0,
                    "name": { "$rtrim": { "input": "$name", "chars": " *" } },
                    "age": 1
                }
            }
        ]

        results = collection.aggregate(pipeline)

        for doc in results:
            print(doc)

    except Exception as e:
        print(f"An error occurred: {e}")

    finally:
        client.close()

example()