Django MongoDB Backend Quickstart

May 6, 2025 Anaiya Raisinghani

Interested in diving into our Django MongoDB Backend integration? Follow along with this quickstart to create a Django application, connect that application to a MongoDB deployment, ensure your deployment is hosted on MongoDB Atlas, and interact with the data stored in your database using simple CRUD operations.

How to Make a RAG Application With LangChain4j

May 3, 2025 Tim Kelly

Retrieval-augmented generation, or RAG, introduces some serious capabilities to your large language models (LLMs). These applications can answer questions about your specific corpus of knowledge, while leveraging all the nuance and sophistication of a traditional LLM.

This tutorial will take you through the ins and outs of creating a Q&A chatbot using RAG. The application will:

1. Retrieve data from a MongoDB Atlas database.
2. Embed and store documents as vector embeddings.
3. Use LangChain4j to query the database and augment LLM prompts with the retrieved data.
4. Enable secure, scalable, and efficient AI-powered applications.

If you want to see the completed application, it is available in the GitHub repository.

Migrating From PostgreSQL to MongoDB in a .NET EF Core Application

May 1, 2025 Luce Carter

For many reasons—including scalability, flexibility, and modernization—more and more development teams are looking to migrate away from PostgreSQL to MongoDB. In the past, these teams might have been hesitant if they used Entity Framework Core (EF Core) as their object relational mapper (ORM).

With EF Core being one of the most popular ORMs for .NET development, we received a lot of requests from the community for a provider, and so did Microsoft! So it made sense for MongoDB to develop a provider for EF Core. This went generally available (GA) in May 2024 and has been greatly received by the community.

Plus, developers can now use MongoDB's Relational Migrator, a free tool that uses smart algorithms and GenAI to streamline migrating from legacy relational databases to MongoDB, accelerating application modernization initiatives. So now is a great time to take a look at how you too can reap the benefits of all this by migrating your .NET application that uses PostgreSQL with EF Core, to use the MongoDB EF Core Provider.

In this tutorial, we will start off with a simple application that uses PostgreSQL as the database under the hood, and update it to still take advantage of EF Core but use MongoDB instead. So let's get started!

Data Modeling for Java Developers: Structuring With PostgreSQL and MongoDB

April 27, 2025 Aasawari Sahasrabuddhe

Application and system designs have always been considered the most essential step in application development. All the later steps and technologies to be used depend on how the system has been designed. If you are a Java developer, choosing the right approach can mean distinguishing between a rigid, complex schema and a nimble, scalable solution. If you are a Java developer who works with PostgreSQL or other relational databases, you understand the pain of representing the many-to-many relationships between the tables.

This tutorial will ease your pain with these or other relationships defined in databases by making use of a document database, MongoDB.

In this article, we’ll understand both approaches, contrasting PostgreSQL’s relational rigour with MongoDB’s document-oriented simplicity. You’ll learn how to weigh trade-offs like ACID compliance versus scalability and discover why MongoDB’s design might save you time.

Build a Basic CRUD Application With Flask-PyMongo

April 26, 2025 Anaiya Raisinghani

In this tutorial, we will dive head first into utilizing MongoDB’s Flask-PyMongo library! We will build a basic CRUD (create, read, update, delete) Flask-PyMongo application and learn about how intuitive this library is for building fully functional Flask applications.

Getting Started With Queryable Encryption in the MongoDB C# Driver

April 22, 2025 Luce Carter

With the release of MongoDB 7.0 in August 2023, we introduced a feature called Queryable Encryption, the first of its kind. With queryable encryption, your data is encrypted, even at rest, with the server unable to read it either but still able to execute queries against it. You can specify what fields to encrypt so you can encrypt as much or as little of your document as you need.

The great news is, not only is this available for all tiers, but it is supported in our C# driver too!

In this tutorial, we are going to add queryable encryption to a healthcare application, ensuring that private information, such as social security number (SSN) and date of birth, is encrypted.

Building a Real-Time AI Fraud Detection System with Spring Kafka and MongoDB

April 21, 2025 Tim Kelly

In this tutorial, we'll build a real-time fraud detection system using MongoDB Atlas Vector Search, Apache Kafka, and AI-generated embeddings. We'll demonstrate how MongoDB Atlas Vector Search can be used to detect anomalies in a stream of financial transactions by analyzing a user's transaction history and identifying suspicious behavior based on LLM-generated embeddings.

Our solution will monitor MongoDB Change Streams using the Java synchronous driver, triggering vector searches on each new transaction to detect potential fraud. While this approach works well for our demo, and for many use cases, we’ll also discuss its limitations. Throughout the tutorial, I’ll cover alternative strategies to optimize performance, whether you need higher transaction throughput, faster fraud detection, or a more scalable architecture.