MongoDB Online Test

1. What is the role of a load balancer in a sharded cluster setup in MongoDB?

Data storage Query optimization Distributing client requests Managing replica sets

2. How can you secure a MongoDB installation with authentication?

Use a username and password Enable SSL/TLS Restrict IP access All of the above

3. What is the MongoDB equivalent of the SQL "SELECT * FROM collection" statement?

db.collection.find() db.collection.get() db.collection.query() db.collection.select()

4. How can you optimize write performance in MongoDB for high-throughput insert operations?

Use a single document for all inserts Use sharding Disable the storage engine Write data asynchronously

5. In MongoDB aggregation, what does the "$group" stage do?

Filters documents Projects data fields Groups documents Sorts documents

6. What does the $project operator do in MongoDB Aggregation?

Filters documents Transforms data Sorts documents Groups documents

7. How does MongoDB Atlas handle automatic backups of your data?

It doesn't support automatic backups Daily and continuous backups Weekly backups only Monthly snapshots

8. How does MongoDB driver authentication typically work?

By using a shared key Through SSL/TLS encryption With a username and password By matching document IDs

9. What is the primary purpose of sharding in MongoDB?

Data encryption Data modeling Horizontal scalability Data replication

10. What does the "reduce" function in MapReduce do?

Combine and reduce results Filter documents Sort the data Encrypt data

11. What is a primary use case for MongoDB in terms of data flexibility and scalability?

Handling large volumes of unstructured data Complex queries Data consistency Small-scale applications

12. What is the primary purpose of the MongoDB Aggregation Framework?

Data retrieval Data storage Data insertion Data modeling

13. Which write concern level ensures that data is written to the primary node and at least one secondary node before acknowledging the write operation?

Majority Unacknowledged Acknowledged Writable

14. In MongoDB, what does the "upsert" option do when updating a document?

Inserts a new document if no match is found Deletes the document Replaces the document Has no effect

15. In a multi-document transaction, when should you explicitly commit or abort the transaction in MongoDB?

After every operation At the end of the transaction Only if there's an error Before the transaction starts

16. Which MongoDB index type allows for fast retrieval of documents based on a single field?

Compound Index Single-field Index Multi-key Index Text Index

17. In MongoDB, how can you optimize performance when working with large result sets?

Use the "batchSize" option Use the "sort" option Increase the number of documents per batch Use the "count" command

18. Which command is used to access the MongoDB shell?

mongo mongod mongosh mongo-client

19. How does GridFS store large files in MongoDB?

As separate documents In a single document In a separate collection As a single string

20. What does BSON stand for in the context of MongoDB?

Binary-Structured Binary JSON Basic Object Notation Binary Serialized