MongoDB and Express.js Quiz

MongoDB stores data in which format?

• Tables

• JSON-like Documents

• CSV

• Key-Value pairs

The default port for MongoDB is:

• 8080

• 27017

• 3000

• 5000

A group of MongoDB documents is called:

• Schema

• Table

• Collection

• Record

Which command shows all databases in MongoDB?

• show collections

• show dbs

• db.show()

• get databases

What is the default _id field in MongoDB?

• UUID

• Auto-increment integer

• ObjectId

• String

Which operator is used to match values in an array?

• $in

• $or

• $set

• $eq

In MongoDB, indexes improve:

• Performance of queries

• Storage size

• Data security

• Schema validation

Which command inserts a single document?

• db.collection.saveOne()

• db.collection.insertOne()

• db.collection.add()

• db.collection.push()

To delete all documents in a collection, use:

• db.collection.drop()

• db.collection.remove({})

• db.collection.deleteMany({})

• Both b & c

MongoDB is classified as a:

• Relational database

• NoSQL database

• Graph database

• Time-series database