What is MongoDB?

• A. A relational database
• B. A NoSQL document database
• C. A front-end library
• D. A programming language

What format does MongoDB use to store documents?

• A. XML
• B. CSV
• C. BSON
• D. YAML

What is the basic unit of data in MongoDB?

• A. Table
• B. Document
• C. Row
• D. Column

Which command is used to insert one document?

• A. insertDocument()
• B. add()
• C. insertOne()
• D. save()

Which MongoDB component stores collections of documents?

• A. Table
• B. Row
• C. Collection
• D. File

Which operator in MongoDB is used to match values in an array?

• A. $match
• B. $in
• C. $eq
• D. $array

What does the $gt operator do?

• A. Finds values greater than a specified value
• B. Groups documents
• C. Grants access
• D. Deletes values

Which of the following is used to validate schema in MongoDB?

• A. JSON Rules
• B. Validation Schema
• C. JSON Schema
• D. BSON Checker

What’s the main purpose of the $project stage in aggregation?

• A. Filter documents
• B. Rename and include fields
• C. Sort data
• D. Group records

Which of the following creates a compound index?

• A. createIndex({name: 1})
• B. createIndex({name: 1, age: -1})
• C. createCompoundIndex()
• D. makeIndex(name, age)

What is the main purpose of replica sets in MongoDB?

• To manage schema
• To create indexes
• To ensure high availability
• To shard data

Which command initializes a replica set?

• rs.start()
• rs.createSet()
• rs.initiate()
• rs.begin()

What is a suitable use case for sharding in MongoDB?

• Low traffic apps
• Single server environments
• Small datasets
• Horizontally scaling large data

What role do config servers play in MongoDB sharding?

• Store backups
• Manage schema
• Track metadata and routing
• Index data

Which component routes queries in a sharded cluster?

• Config Server
• Mongo Shell
• Mongos
• Primary Node