star iconstar iconstar iconstar iconstar icon

"Huge timesaver. Worth the money"

star iconstar iconstar iconstar iconstar icon

"It's an excellent tool"

star iconstar iconstar iconstar iconstar icon

"Fantastic catalogue of questions"

Ace your next tech interview with confidence

Explore our carefully curated catalog of interview essentials covering full-stack, data structures and alogithms, system design, data science, and machine learning interview questions

MongoDB

100 MongoDB interview questions

Only coding challenges
Topic progress: 0%

MongoDB Fundamentals


  • 1.

    What is MongoDB and what are its main features?

    Answer:
  • 2.

    How does MongoDB differ from relational databases?

    Answer:
  • 3.

    Can you describe the structure of data in MongoDB?

    Answer:
  • 4.

    What is a Document in MongoDB?

    Answer:
  • 5.

    How is data stored in collections in MongoDB?

    Answer:
  • 6.

    Describe what a MongoDB database is.

    Answer:
  • 7.

    What is the default port on which MongoDB listens?

    Answer:
  • 8.

    How does MongoDB provide high availability and disaster recovery?

    Answer:
  • 9.

    What are indexes in MongoDB, and why are they used?

    Answer:
  • 10.

    What is the role of the id field in MongoDB documents?

    Answer:

CRUD Operations


  • 11.

    How do you create a new MongoDB collection?

    Answer:
  • 12.

    What is the syntax to insert a document into a MongoDB collection?

    Answer:
  • 13.

    Describe how to read data from a MongoDB collection.

    Answer:
  • 14.

    Explain how to update documents in MongoDB.

    Answer:
  • 15.

    What are the MongoDB commands for deleting documents?

    Answer:
  • 16.

    Can you join two collections in MongoDB? If so, how?

    Lock icon indicating premium question
    Answer:
  • 17.

    How do you limit the number of documents returned by a MongoDB query?

    Lock icon indicating premium question
    Answer:
  • 18.

    What is the difference between find() and findOne() in MongoDB?

    Lock icon indicating premium question
    Answer:
  • 19.

    How can you achieve pagination in MongoDB?

    Lock icon indicating premium question
    Answer:
  • 20.

    What are the differences between MongoDB’s insertOne and insertMany methods?

    Lock icon indicating premium question
    Answer:

Indexing and Aggregation


  • 21.

    Describe a compound index in MongoDB.

    Lock icon indicating premium question
    Answer:
  • 22.

    What is the aggregation pipeline in MongoDB?

    Lock icon indicating premium question
    Answer:
  • 23.

    How can you create an index in MongoDB and when should you do it?

    Lock icon indicating premium question
    Answer:
  • 24.

    Explain how MongoDB’s $match, $group and $sort operators work in an aggregation pipeline.

    Lock icon indicating premium question
    Answer:
  • 25.

    What is the purpose of the explain() method?

    Lock icon indicating premium question
    Answer:

Replication and Sharding


  • 26.

    Can you explain MongoDB’s replication?

    Lock icon indicating premium question
    Answer:
  • 27.

    Describe the purpose and components of a replica set.

    Lock icon indicating premium question
    Answer:
  • 28.

    What is sharding in MongoDB and when would you use it?

    Lock icon indicating premium question
    Answer:
  • 29.

    How does MongoDB perform automatic failover?

    Lock icon indicating premium question
    Answer:
  • 30.

    Describe the difference between horizontal scaling and vertical scaling, and how MongoDB supports them.

    Lock icon indicating premium question
    Answer:

Performance and Optimization


  • 31.

    How does MongoDB handle large data volumes?

    Lock icon indicating premium question
    Answer:
  • 32.

    What strategies can you use to diagnose and address performance issues in MongoDB?

    Lock icon indicating premium question
    Answer:
  • 33.

    How do you ensure that indexes fit into RAM?

    Lock icon indicating premium question
    Answer:
  • 34.

    Can you explain MongoDB’s write concern?

    Lock icon indicating premium question
    Answer:
  • 35.

    What is a covered query in MongoDB?

    Lock icon indicating premium question
    Answer:

MongoDB Security


  • 36.

    What are the security features available in MongoDB?

    Lock icon indicating premium question
    Answer:
  • 37.

    How do you enable authentication in MongoDB?

    Lock icon indicating premium question
    Answer:
  • 38.

    Describe role-based access control in MongoDB.

    Lock icon indicating premium question
    Answer:
  • 39.

    Explain how to encrypt MongoDB data.

    Lock icon indicating premium question
    Answer:
  • 40.

    Can you set up MongoDB to use TLS/SSL for connections?

    Lock icon indicating premium question
    Answer:

MongoDB Storage Engines


  • 41.

    What are the different storage engines available in MongoDB?

    Lock icon indicating premium question
    Answer:
  • 42.

    How does the WiredTiger storage engine differ from MMAPv1?

    Lock icon indicating premium question
    Answer:
  • 43.

    Can you switch between storage engines in a MongoDB database?

    Lock icon indicating premium question
    Answer:

Advanced MongoDB Concepts


  • 44.

    What is the oplog in MongoDB, and how does it work?

    Lock icon indicating premium question
    Answer:
  • 45.

    How do you use the $lookup operator in MongoDB?

    Lock icon indicating premium question
    Answer:
  • 46.

    Can you explain the role of a mongos server in a sharded MongoDB architecture?

    Lock icon indicating premium question
    Answer:
  • 47.

    What is journaling in MongoDB and why is it important?

    Lock icon indicating premium question
    Answer:
  • 48.

    Explain the GridFS specification in MongoDB.

    Lock icon indicating premium question
    Answer:

MongoDB Schema Design


  • 49.

    How does schema design impact performance in MongoDB?

    Lock icon indicating premium question
    Answer:
  • 50.

    Compare embedding vs. linking documents in MongoDB.

    Lock icon indicating premium question
    Answer:
  • 51.

    What factors do you consider when designing a schema for MongoDB?

    Lock icon indicating premium question
    Answer:
  • 52.

    How do you handle one-to-many relationships in MongoDB data modeling?

    Lock icon indicating premium question
    Answer:

MongoDB Management and Maintenance


  • 53.

    How do you perform backups in MongoDB?

    Lock icon indicating premium question
    Answer:
  • 54.

    What techniques can be used to restore a MongoDB database?

    Lock icon indicating premium question
    Answer:
  • 55.

    How would you monitor the performance of a MongoDB instance?

    Lock icon indicating premium question
    Answer:
  • 56.

    What factors would lead you to defragment a MongoDB collection?

    Lock icon indicating premium question
    Answer:

Working with Data Types


  • 57.

    What are the different data types supported in MongoDB?

    Lock icon indicating premium question
    Answer:
  • 58.

    How does MongoDB store different types of numerical data?

    Lock icon indicating premium question
    Answer:
  • 59.

    How does MongoDB handle DateTime data types?

    Lock icon indicating premium question
    Answer:
  • 60.

    Can you store multimedia files directly in MongoDB?

    Lock icon indicating premium question
    Answer:

MongoDB and Programming


  • 61.

    How do you connect to a MongoDB database from a Python script?

    Lock icon indicating premium question
    Answer:
  • 62.

    What is Mongoose and how does it relate to MongoDB?

    Lock icon indicating premium question
    Answer:
  • 63.

    Can you create and use stored procedures in MongoDB?

    Lock icon indicating premium question
    Answer:
  • 64.

    Describe how to use the Mongo Shell for database operations.

    Lock icon indicating premium question
    Answer:

MongoDB Drivers and ODMs


  • 65.

    What is the purpose of MongoDB ODM / ORM frameworks?

    Lock icon indicating premium question
    Answer:
  • 66.

    How can you perform MongoDB operations using Node.js?

    Lock icon indicating premium question
    Answer:
  • 67.

    List some popular libraries for integrating MongoDB with web applications.

    Lock icon indicating premium question
    Answer:

MongoDB and Big Data


  • 68.

    How is MongoDB used in big data analytics?

    Lock icon indicating premium question
    Answer:
  • 69.

    Can MongoDB handle real-time analytics workloads?

    Lock icon indicating premium question
    Answer:
  • 70.

    How do you stream large quantities of data into and out of MongoDB?

    Lock icon indicating premium question
    Answer:

MongoDB Internals


  • 71.

    How does MongoDB handle locking and concurrency?

    Lock icon indicating premium question
    Answer:
  • 72.

    What is the relationship between BSON and MongoDB?

    Lock icon indicating premium question
    Answer:
  • 73.

    Can you explain the concept of a cursor in MongoDB?

    Lock icon indicating premium question
    Answer:
  • 74.

    How does MongoDB manage memory?

    Lock icon indicating premium question
    Answer:

MongoDB Deployment


  • 75.

    What are some best practices for securing a MongoDB instance?

    Lock icon indicating premium question
    Answer:
  • 76.

    How do you scale a MongoDB deployment?

    Lock icon indicating premium question
    Answer:
  • 77.

    What is Ops Manager in MongoDB?

    Lock icon indicating premium question
    Answer:

MongoDB Errors and Troubleshooting


  • 78.

    How do you troubleshoot a slow-running query in MongoDB?

    Lock icon indicating premium question
    Answer:
  • 79.

    What could cause a MongoServerError: E11000 duplicate key error?

    Lock icon indicating premium question
    Answer:
  • 80.

    How would you handle a scenario where the MongoDB service won’t start?

    Lock icon indicating premium question
    Answer:

MongoDB in the Cloud


  • 81.

    What are some MongoDB cloud-hosted solutions?

    Lock icon indicating premium question
    Answer:
  • 82.

    How does MongoDB Atlas enhance MongoDB capabilities?

    Lock icon indicating premium question
    Answer:

API and Tools


  • 83.

    Describe the use of Compass in MongoDB.

    Lock icon indicating premium question
    Answer:
  • 84.

    Explain the use of Robo 3T (formerly Robomongo).

    Lock icon indicating premium question
    Answer:
  • 85.

    Can you work with MongoDB using the command line? If so, how?

    Lock icon indicating premium question
    Answer:

Contemporary MongoDB Challenges and Considerations


  • 86.

    What factors to consider when deploying MongoDB in a containerized environment?

    Lock icon indicating premium question
    Answer:
  • 87.

    How does MongoDB work with microservices architectures?

    Lock icon indicating premium question
    Answer:
  • 88.

    What are change streams in MongoDB?

    Lock icon indicating premium question
    Answer:

MongoDB Updates and Evolution


  • 89.

    What major features were added in the latest MongoDB release?

    Lock icon indicating premium question
    Answer:
  • 90.

    How does MongoDB handle version upgrades in a production environment?

    Lock icon indicating premium question
    Answer:

Use Cases for MongoDB


  • 91.

    In what scenarios is MongoDB favored over a relational database?

    Lock icon indicating premium question
    Answer:
  • 92.

    What are some common patterns of data access in applications that use MongoDB?

    Lock icon indicating premium question
    Answer:

MongoDB Query Optimization


  • 93.

    How can you prevent slow queries in MongoDB?

    Lock icon indicating premium question
    Answer:
  • 94.

    Explain the role of the Profiler in MongoDB.

    Lock icon indicating premium question
    Answer:
  • 95.

    How are B-tree indexes implemented in MongoDB?

    Lock icon indicating premium question
    Answer:

Advanced Queries and Data Processing


  • 96.

    How do you handle complex transactions in MongoDB?

    Lock icon indicating premium question
    Answer:
  • 97.

    Explain the MongoDB MapReduce operation.

    Lock icon indicating premium question
    Answer:
  • 98.

    Can you perform text searches in MongoDB?

    Lock icon indicating premium question
    Answer:

MongoDB Integration


  • 99.

    How can you integrate MongoDB with third-party applications?

    Lock icon indicating premium question
    Answer:
  • 100.

    Describe how to synchronize data between SQL databases and MongoDB.

    Lock icon indicating premium question
    Answer:
folder icon

Unlock interview insights

Get the inside track on what to expect in your next interview. Access a collection of high quality technical interview questions with detailed answers to help you prepare for your next coding interview.

graph icon

Track progress

Simple interface helps to track your learning progress. Easily navigate through the wide range of questions and focus on key topics you need for your interview success.

clock icon

Save time

Save countless hours searching for information on hundreds of low-quality sites designed to drive traffic and make money from advertising.

Land a six-figure job at one of the top tech companies

amazon logometa logogoogle logomicrosoft logoopenai logo
Ready to nail your next interview?

Stand out and get your dream job

scroll up button

Go up