Learn MongoDB basics, CRUD, querying, data modeling, indexing, and aggregation through hands-on practice, no advanced programming required.

Become a MERN Stack Developer

In this module, you'll dive into MongoDB, the document-oriented, NoSQL database that powers the MERN stack. You’ll explore how its flexible schema design supports rapid iteration and scalability for modern web applications.

Starting with core concepts like databases, collections, and documents, you'll learn to perform CRUD operations efficiently using practical, real-world examples. As you progress, you'll master advanced querying with filters, projections, and operators to extract meaningful insights from your data.

The module also covers key performance techniques, including index optimization and schema design best practices. You'll gain hands-on experience with the aggregation framework for data analysis, and learn to manage your data using import/export tools and backup strategies, skills critical for building and maintaining production-grade MERN applications.

MongoDB Essentials for MERN Stack Development

Prevents documents with missing required fields

Helps maintain a consistent data structure

**(Select all that apply.)** What is a benefit of using JSON Schema validation in MongoDB? 

(Select all that apply.) What is a benefit of using JSON Schema validation in MongoDB?

The document is inserted, but a warning is shown.

The document is rejected and an error is returned.

The missing field is automatically added with a default value.

The document is inserted, but only if you are an admin.

What happens if you try to insert a document into a collection with schema validation, but the document is missing a required field?

What happens if you try to insert a document into a collection with schema validation, but the document is missing a required field?

Which role will you assign to a user who needs to read and write data, but should not perform administrative tasks?

Which role will you assign to a user who needs to read and write data, but should not perform administrative tasks?

Authentication checks what actions a user can perform; authorization checks their identity.

Authentication checks a user’s identity; authorization checks what actions they can perform.

What is the difference between authentication and authorization in MongoDB?

What is the difference between authentication and authorization in MongoDB?

```javascript
db.createUser({
 user: "readonly",
 pwd: "password123",
 roles: [ { role: "read", db: "ecommerce" } ]
})
```

```javascript
db.createUser({
 user: "readonly",
 pwd: "password123",
 roles: [ { role: "readWrite", db: "ecommerce" } ]
})
```

```javascript
db.createUser({
 user: "readonly",
 pwd: "password123",
 roles: [ { role: "dbAdmin", db: "ecommerce" } ]
})
```

```javascript
db.createUser({
 user: "readonly",
 pwd: "password123",
 roles: [ { role: "root", db: "admin" } ]
})
```

Which command creates a user with read-only access to the `ecommerce` database?

Which command creates a user with read-only access to the <code>ecommerce</code> database?

A user tries to delete a document but only has the `read` role.

A user tries to log in with the wrong password.

A user tries to insert a document missing a required field.

A user with `readWrite` role tries to update a document.

Which scenario will result in an authorization error in MongoDB?

Which scenario will result in an authorization error in MongoDB?

**(True or False)** If you enable authentication in MongoDB, all users must provide valid credentials to access any database.

(True or False) If you enable authentication in MongoDB, all users must provide valid credentials to access any database.

The user does not have write permissions.

The document does not match the collection’s schema rules.

You see the following error when trying to insert a document: `"Document failed validation"`. What is the most likely cause?

You see the following error when trying to insert a document: <code>&quot;Document failed validation&quot;</code>. What is the most likely cause?

Introduction and Fundamentals

Basic CRUD Operations

Advanced CRUD Operations

Aggregation Framework

Indexing for Performance

Data Modeling and Validation

Importing, Exporting, and Backup

Appendix

Conclusion

Quiz: Data Validation and Security