$regexMatch

New from version 5.0. Not supported by Elastic cluster.

The $regexMatch operator in Amazon DocumentDB is used to perform regular expression matching on string fields. It returns a boolean value (true or false) indicating whether the input string matches the specified pattern.

Parameters

• input: The string to test against the regular expression.

• regex: The regular expression pattern to match.

• options: (Optional) Flags to modify the regular expression behavior, such as case-insensitive matching (i) or multiline matching (m).

Example (MongoDB Shell)

The following example demonstrates how to use the $regexMatch operator to check if names start with the letter 'M'. The operator returns true or false for each document.

Create sample documents

db.users.insertMany([
  { "_id":1, name: "María García", email: "marí[e-mail]" },
  { "_id":2, name: "Arnav Desai", email: "[e-mail]" },
  { "_id":3, name: "Martha Rivera", email: "[e-mail]" },
  { "_id":4, name: "Richard Roe", email: "[e-mail]" },

]);

Query example

db.users.aggregate([
  {
    $project: {
      name: 1,
      startsWithM: {
        $regexMatch: {
          input: "$name",
          regex: "^M",
          options: "i"
        }
      }
    }
  }
]);

Output

{ _id: 1, name: 'María García', startsWithM: true },
{ _id: 2, name: 'Arnav Desai', startsWithM: false },
{ _id: 3, name: 'Martha Rivera', startsWithM: true },
{ _id: 4, name: 'Richard Roe', startsWithM: false }

Code examples

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

Node.js

const { MongoClient } = require('mongodb');

async function checkNamePattern() {
  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('users');

  const result = await collection.aggregate([
    {
      $project: {
        name: 1,
        startsWithM: {
          $regexMatch: {
            input: "$name",
            regex: "^M",
            options: "i"
          }
        }
      }
    }
  ]).toArray();

  console.log(result);

  await client.close();
}

checkNamePattern();

Python

from pymongo import MongoClient

def check_name_pattern():
    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.users

    result = list(collection.aggregate([
        {
            '$project': {
                'name': 1,
                'startsWithM': {
                    '$regexMatch': {
                        'input': '$name',
                        'regex': '^M',
                        'options': 'i'
                    }
                }
            }
        }
    ]))

    print(result)

    client.close()

check_name_pattern()