MongoDB Quiz - MCQ - Multiple Choice Questions

Q. What is MongoDB?

A. A relational database management system
B. An object-oriented database
C. A document-oriented NoSQL database
D. A graph database
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Q. What type of data model does MongoDB use?

A. Key-value model
B. Document model
C. Graph model
D. Relational model
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Q. How does MongoDB handle relationships between data?

A. By using foreign keys and joins
B. Through embedded documents and references
C. With indexes and links
D. By utilizing graph structures
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Q. What is a collection in MongoDB?

A. A set of documents with similar structure
B. A grouping of related tables
C. A unique identifier for a document
D. A database index
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Q. How does MongoDB ensure data consistency?

A. Through transactions and ACID compliance
B. By using eventual consistency
C. With document locking
D. Through replication and write concerns
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Q. What is sharding in MongoDB?

A. Distributing data across multiple machines for scalability
B. A technique for data compression
C. A method for securing data with encryption
D. A process of optimizing query performance
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Q. How does MongoDB handle schema design?

A. With a rigid schema defined upfront
B. Through a flexible schema that can evolve over time
C. By dynamically creating a schema based on data
D. With a user-defined schema for each collection
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Q. What is the role of the MongoDB Query Language (MQL)?

A. To perform complex queries and aggregations
B. To define indexes and optimize query performance
C. To manage security and access control
D. To handle data replication and sharding
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Q. How does MongoDB handle data replication?

A. Through master-slave replication
B. By using multi-master replication
C. With asynchronous replication
D. All of the above
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Q. What is a replica set in MongoDB?

A. A group of MongoDB instances that hold the same data set
B. A configuration for sharding data across multiple machines
C. A set of indexes used for optimizing query performance
D. A security feature that encrypts data at rest
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Q. How does MongoDB handle data indexing?

A. Through unique indexes on primary keys
B. By allowing custom indexes on any field or combination of fields
C. With automatically generated indexes for frequently queried fields
D. All of the above
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Q. What is MongoDB Atlas?

A. A cloud-based database-as-a-service platform for MongoDB
B. A graphical user interface tool for managing MongoDB
C. A command-line interface for interacting with MongoDB
D. A set of development tools for building MongoDB applications
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Q. How does MongoDB handle data security?

A. Through authentication and authorization mechanisms
B. By providing encryption at rest and in transit
C. With role-based access control (RBAC)
D. All of the above
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Q. What is a pipeline in MongoDB?

A. A set of data processing steps for transforming data
B. A mechanism for parallelizing data processing
C. A technique for optimizing data transfer
D. A method for error handling in data processing
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Q. How does MongoDB handle data backups?

A. Through manual file-system level backups
B. By providing point-in-time recovery capabilities
C. With continuous data replication to a backup server
D. All of the above
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Q. Which of the following code snippets is used to connect to a MongoDB database named "mydb" on a local host using the MongoClient class?

A.

MongoClient client = new MongoClient("localhost", 27017);
MongoDatabase db = client.getDatabase("mydb");

B.

MongoClientURI uri = new MongoClientURI("mongodb://localhost:27017/mydb");
MongoClient client = new MongoClient(uri);
MongoDatabase db = client.getDatabase("mydb");

C.

MongoClient client = new MongoClient("localhost", "mydb");
MongoDatabase db = client.getDatabase();

D.

MongoClient client = new MongoClient("localhost:27017");
MongoDatabase db = client.getDatabase("mydb");

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Q. Which of the following code snippets demonstrates the creation of a MongoCollection object for a collection named "mycollection" in the "mydb" database?

A.

MongoCollection<Document> collection = db.getCollection(mycollection);

B.

MongoCollection collection = db.getCollection(mycollection);

C.

MongoCollection<Document> collection = db.collection(mycollection);

D.

MongoCollection<Document> collection = db.get("mycollection");

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Q. Which of the following code snippets demonstrates the insertion of a new document into the "mycollection" collection?

A.

Document document = new Document("name", "John")
                        .append("age", 30)
                        .append("city", "New York");
collection.insertOne(document);

B.

BasicDBObject document = new BasicDBObject("name", "John")
                              .append("age", 30)
                              .append("city", "New York");
collection.insertOne(document);

C.

Document document = new Document();
document.put("name", "John");
document.put("age", 30);
document.put("city", "New York");
collection.insertOne(document);

D.

Document document = Document.parse("{name: 'John', age: 30, city: 'New York'}");
collection.insertOne(document);

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Q. Which of the following code snippets demonstrates the correct way to perform a find operation and return all documents from the "mycollection" collection?

A.

FindIterable<Document> iterable = collection.find();
iterable.into(new ArrayList<>());

B.

List<Document> documents = collection.find().into(new ArrayList<>());

C.

List<Document> documents = collection.find().toList();

D.

FindIterable<Document> iterable = collection.find();
List<Document> documents = iterable.into(Documents.asList());

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Q. Which of the following code snippets demonstrates the correct way to update all documents in the "mycollection" collection by incrementing the "age" field by 1?

A.

collection.updateMany(new Document(), new Document("$inc", new Document("age", 1)));

B.

collection.update(new Document(), new Document("$inc", new Document("age", 1)), UpdateOptions.multi(true));

C.

collection.updateMany(new Document(), new Document("$set", Field.name("age").setValue(1)));

D.

collection.update(new Document(), new Document("$inc", Field.name("age").inc(1)), UpdateOptions.multi(true));

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Q. Which of the following code snippets demonstrates the correct way to delete all documents from the "mycollection" collection where the "age" field is greater than 30?

A.

collection.deleteMany(new Document("age", new Document("$gt", 30)));

B.

collection.remove(new Document("age", new Document("$gt", 30)));

C.

collection.remove(new Document("age", ">" + 30));

D.

collection.delete(new Document("age", new Document("$gt", 30)));

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Q. Which of the following code snippets demonstrates the correct way to create an index on the "name" field in the "mycollection" collection?

A.

collection.createIndex(new Document("name", 1));

B.

collection.createIndex(Field.name("name"));

C.

collection.createIndex(Indexes.ascending("name"));

D.

collection.createIndex("name");

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Q. Which of the following code snippets demonstrates the correct way to aggregate documents in the "mycollection" collection and group them by the "city" field?

A.

AggregationPipeline pipeline = Aggregation.group("city");
List<Document> results = collection.aggregate(pipeline).into(new ArrayList<>());

B.

Aggregation pipeline = collection.aggregate(Aggregation.group("city"));
List<Document> results = pipeline.getMappedResults(Document.class);

C.

Aggregation pipeline = Aggregation.group("city").into(new ArrayList<Document>());
List<Document> results = collection.aggregate(pipeline);

D.

Aggregation aggregation = new Aggregation(Aggregation.group("city"));
List<Document> results = collection.aggregate(aggregation, Document.class).getMappedResults();

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Q. Which of the following code snippets demonstrates the correct way to count the number of documents in the "mycollection" collection that match a specific condition?

A.

long count = collection.countDocuments(new Document("age", new Document("$gt", 30)));

B.

long count = collection.count(new Document("age", ">" + 30));

C.

long count = collection.count(Filters.gt("age", 30));

D.

long count = collection.count(new Document("$match", new Document("age", new Document("$gt", 30))));

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Q. Which of the following code snippets demonstrates the correct way to drop the "mycollection" collection from the database?

A.

collection.drop();

B.

db.dropCollection("mycollection");

C.

collection.dropCollection();

D.

db.collection("mycollection").drop();

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