Ultimate Mongodb Test - 78+ MCQs: MongoDB test: Assess Your Knowledge with MongoDB Questions and Answers

1. What is the role of the WiredTiger storage engine in MongoDB?

Data encryption

Query optimization

Journaling

Storage and retrieval of data

2. In MongoDB, what is a capped collection?

A collection with a maximum size

A collection with predefined documents

A collection with nested documents

A collection with unlimited storage

3. Which command is used to create a new database in MongoDB?

db.makeDatabase()

db.new()

db.createDatabase()

use <databaseName>

4. Which operator is used for equality in MongoDB queries?

$eq

$equals

$eqs

$equal

5. How does MongoDB handle data consistency in a distributed environment?

Eventual consistency

Data compression

Data validation

Immediate consistency

6. In MongoDB, what is the purpose of the `$nin` operator?

Matches values not in a specified array

Matches values in a specified array

Negates the results of an aggregation stage

Selects documents with a not-in condition

7. How can you perform an upsert operation in MongoDB?

db.updateOne()

db.insert()

db.save()

db.upsert()

8. Which command is used to remove a document from a collection in MongoDB?

db.erase()

db.remove()

db.delete()

db.drop()

9. What is the purpose of the `db.currentOp()` method in MongoDB?

To create a new operation

To retrieve information about current operations

To update an existing operation

To terminate an operation

10. What does the term 'BSON' stand for in MongoDB?

Binary Structured Object Notation

Basic Structured Object Notation

Boolean Structured Object Notation

Binary System Object Notation

11. What is the purpose of the `db.killOp()` method in MongoDB?

To terminate a specific operation

To create a new operation

To update an existing operation

To retrieve information about current operations

12. What is the purpose of the `$elemMatch` operator in MongoDB?

Matches arrays with a specific element

Matches arrays with all specified elements

Matches arrays without a specific element

Matches arrays based on position

13. How does MongoDB ensure high availability in a replica set?

Automated backups

Data partitioning

Data mirroring

Failover mechanism

14. What is the purpose of the `ttl` index type in MongoDB?

To store timestamps

To perform text search

To create a time-to-live index

To encrypt data

15. In MongoDB, what is the primary purpose of the `oplog`?

To store binary data

To record all write operations

To optimize query performance

To manage database users

16. In MongoDB, what is the primary role of the `mongos` process?

Client application for MongoDB

MongoDB database server

Query optimizer

Shard router in a sharded cluster

17. What is the purpose of the $redact stage in MongoDB aggregation?

Data transformation

Data security

Data validation

Query optimization

18. Explain the significance of the ObjectId in MongoDB documents.

Primary key

Timestamp

Foreign key

Random identifier

19. What is the purpose of the `explain()` method in MongoDB?

To provide documentation for queries

To analyze and report on the query execution plan

To debug MongoDB server issues

To format query results

20. What is the purpose of the explain() method in MongoDB?

Data retrieval details

Data encryption

Data compression

Data validation

MongoDB MCQ Test 4