MongoDB MCQs and Answers With Explanation – MongoDB is a popular NoSQL database that uses a document-oriented data model to store data and is widely used for its scalability, flexibility, and performance. This set of MongoDB MCQ Questions And Answers covers various aspects of the MongoDB database. Kindly check out this MongoDB MCQ Quiz/ MongoDB Multiple Choice Questions and enhance your knowledge about the MongoDB concept.
MongoDB Multiple Choice Questions
The starting questions ask about the type of database MongoDB is, and the rest of the questions delve into the specific concepts and operations in MongoDB, such as sharding, BSON, collections, replica sets, cursor, operators, and commands. Each question has four options, and the correct answer is highlighted with an explanation. This MongoDB MCQ Online Quiz Test/ MongoDB Online Quiz is useful for anyone preparing for a MongoDB certification exam or interview or wanting to assess their understanding of MongoDB.
MongoDB MCQ Questions And Answers
Name | MongoDB |
Exam Type | MCQ (Multiple Choice Questions) |
Category | Technical Quiz |
Mode of Quiz | Online |
Top 30 MongoDB MCQs | Practice Online Quiz
1. Which of the following is a NoSQL database?
a) MySQL
b) MongoDB
c) Oracle
d) SQL Server
Answer: b) MongoDB
Explanation: MongoDB is a NoSQL database that uses a document-oriented data model to store data. Unlike traditional relational databases like MySQL and SQL Server, MongoDB does not rely on tables and rows to organize and store data.
2. What is a MongoDB database?
a) A group of related collections
b) A group of related documents
c) A group of related tables
d) A group of related data values
Answer: a) A group of related collections
Explanation: A MongoDB database is a group of related collections. Each collection is stored in its own file, and multiple collections can be grouped together in a single database.
3. What is sharding in MongoDB?
a) Splitting a database into smaller, more manageable pieces called shards
b) Combining multiple databases into a single, unified database
c) Creating a backup copy of a database for disaster recovery purposes
d) None of the above
Answer: a) Splitting a database into smaller, more manageable pieces called shards
Explanation: Sharding is a technique used in MongoDB to horizontally partition a database into smaller, more manageable pieces called shards. Each shard contains a subset of the data and runs on a separate server or cluster.
4. What is a BSON in MongoDB?
a) A type of data structure used to store data in MongoDB
b) A query language used to retrieve data from MongoDB
c) A command used to create a new database in MongoDB
d) None of the above
Answer: a) A type of data structure used to store data in MongoDB
Explanation: BSON (Binary JSON) is a type of data structure used by MongoDB to store and manipulate data. It is similar to JSON (JavaScript Object Notation), but supports additional data types such as Date and Binary.
5. Which of the following is a collection in MongoDB?
a) A group of related documents
b) A group of related tables
c) A group of related fields
d) None of the above
Answer: a) A group of related documents
Explanation: In MongoDB, a collection is a group of related documents. Documents in a collection are similar to rows in a table in a relational database and are stored in BSON format.
6. What is a replica set in MongoDB?
a) A group of MongoDB instances that maintain the same data set
b) A type of query used to retrieve data from MongoDB
c) A type of index used to improve query performance
d) None of the above
Answer: a) A group of MongoDB instances that maintain the same data set
Explanation: A replica set is a group of MongoDB instances that maintain the same data set. One instance serves as the primary node that receives all write operations, while the other nodes serve as secondary nodes that replicate the data from the primary node.
7. What is a cursor in MongoDB?
a) A temporary variable used to store query results
b) A pointer to the result set of a query
c) A type of index used to improve query performance
d) None of the above
Answer: b) A pointer to the result set of a query
Explanation: In MongoDB, a cursor is a pointer to the result set of a query. Cursors are used to iterate over large result sets and fetch documents one by one.
8. Which of the following is a command used to create a new database in MongoDB?
a) INSERT
b) UPDATE
c) DELETE
d) None of the above
Answer: d) None of the above
Explanation: In MongoDB, databases are not explicitly created. Instead, they are created automatically when data is inserted into a collection that does not yet exist.
9. What is the use of the $push operator in MongoDB?
a) To add a new document to a collection
b) To add a new field to a document
c) To add an element to the end of an array
d) None of the above
Answer: c) To add an element to the end of an array
Explanation: The $push operator is used in MongoDB to add an element to the end of an array. If the field does not exist, $push creates the field with the specified value as an array.
10. What is the use of the $pull operator in MongoDB?
a) To remove an element from an array
b) To remove a document from a collection
c) To remove a field from a document
d) None of the above
Answer: a) To remove an element from an array
Explanation: The $pull operator is used in MongoDB to remove an element from an array that matches a specified condition.
11. What is the use of the $inc operator in MongoDB?
a) To increment the value of a field by a specified amount
b) To insert a new document into a collection
c) To remove a field from a document
d) None of the above
Answer: a) To increment the value of a field by a specified amount
Explanation: The $inc operator is used in MongoDB to increment the value of a field by a specified amount. If the field does not exist, $inc creates the field with the specified value.
12. What is the use of the $set operator in MongoDB?
a) To set the value of a field in a document
b) To insert a new document into a collection
c) To remove a field from a document
d) None of the above
Answer: a) To set the value of a field in a document
Explanation: The $set operator is used in MongoDB to set the value of a field in a document. If the field does not exist, $set creates the field with the specified value.
13. What is the use of the $unset operator in MongoDB?
a) To remove a field from a document
b) To remove a document from a collection
c) To set the value of a field in a document to null
d) None of the above
Answer: a) To remove a field from a document
Explanation: The $unset operator is used in MongoDB to remove a field from a document.
14. What is the use of the $rename operator in MongoDB?
a) To rename a collection
b) To rename a field in a document
c) To rename a database
d) None of the above
Answer: b) To rename a field in a document
Explanation: The $rename operator is used in MongoDB to rename a field in a document.
15. What is the use of the $sort operator in MongoDB?
a) To sort the documents in a collection
b) To group documents in a collection based on a specified condition
c) To limit the number of documents returned by a query
d) None of the above
Answer: a) To sort the documents in a collection
Explanation: The $sort operator is used in MongoDB to sort the documents in a collection based on a specified field.
16. What is the use of the $push operator in MongoDB?
a) To add a new document to a collection
b) To add a new field to a document
c) To add an element to the end of an array
d) None of the above
Answer: c) To add an element to the end of an array
Explanation: The $push operator is used in MongoDB to add an element to the end of an array. If the field does not exist, $push creates the field with the specified value as an array.
17. What is the use of the $pull operator in MongoDB?
a) To remove an element from an array
b) To remove a document from a collection
c) To remove a field from a document
d) None of the above
Answer: a) To remove an element from an array
Explanation: The $pull operator is used in MongoDB to remove an element from an array that matches a specified condition.
18. What is the use of the $inc operator in MongoDB?
a) To increment the value of a field by a specified amount
b) To insert a new document into a collection
c) To remove a field from a document
d) None of the above
Answer: a) To increment the value of a field by a specified amount
Explanation: The $inc operator is used in MongoDB to increment the value of a field by a specified amount. If the field does not exist, $inc creates the field with the specified value.
19. What is the use of the $set operator in MongoDB?
a) To set the value of a field in a document
b) To insert a new document into a collection
c) To remove a field from a document
d) None of the above
Answer: a) To set the value of a field in a document
Explanation: The $set operator is used in MongoDB to set the value of a field in a document. If the field does not exist, $set creates the field with the specified value.
20. What is the use of the $unset operator in MongoDB?
a) To remove a field from a document
b) To remove a document from a collection
c) To set the value of a field in a document to null
d) None of the above
Answer: a) To remove a field from a document
Explanation: The $unset operator is used in MongoDB to remove a field from a document.
21. What is the use of the $rename operator in MongoDB?
a) To rename a collection
b) To rename a field in a document
c) To rename a database
d) None of the above
Answer: b) To rename a field in a document
Explanation: The $rename operator is used in MongoDB to rename a field in a document.
22. What is the use of the $sort operator in MongoDB?
a) To sort the documents in a collection
b) To group documents in a collection based on a specified condition
c) To limit the number of documents returned by a query
d) None of the above
Answer: a) To sort the documents in a collection
Explanation: The $sort operator is used in MongoDB to sort the documents in a collection based on a specified field.
23. What is the use of the $limit operator in MongoDB?
a) To sort the documents in a collection
b) To group documents in a collection based on a specified condition
c) To limit the number of documents returned by a query
d) None of the above
Answer: c) To limit the number of documents returned by a query
Explanation: The $limit operator is used in MongoDB to limit the number of documents returned by a query. This can be useful when dealing with large collections to improve query performance and reduce memory usage.
24. What is the use of the $skip operator in MongoDB?
a) To sort the documents in a collection
b) To group documents in a collection based on a specified condition
c) To skip a specified number of documents in the result set
d) None of the above
Answer: c) To skip a specified number of documents in the result set
Explanation: The $skip operator is used in MongoDB to skip a specified number of documents in the result set. This can be useful when implementing pagination.
25. What is the use of the $in operator in MongoDB?
a) To check if a field value matches any value in a specified array
b) To check if a field value does not match any value in a specified array
c) To check if a field value is greater than a specified value
d) None of the above
Answer: a) To check if a field value matches any value in a specified array
Explanation: The $in operator is used in MongoDB to check if a field value matches any value in a specified array. This can be useful when querying for documents that match a set of values.
26. What is the use of the $nin operator in MongoDB?
a) To check if a field value matches any value in a specified array
b) To check if a field value does not match any value in a specified array
c) To check if a field value is greater than a specified value
d) None of the above
Answer: b) To check if a field value does not match any value in a specified array
Explanation: The $nin operator is used in MongoDB to check if a field value does not match any value in a specified array. This can be useful when querying for documents that do not match a set of values.
27. What is the use of the $and operator in MongoDB?
a) To perform a logical AND operation on multiple conditions
b) To perform a logical OR operation on multiple conditions
c) To perform a logical NOT operation on a condition
d) None of the above
Answer: a) To perform a logical AND operation on multiple conditions
Explanation: The $and operator is used in MongoDB to perform a logical AND operation on multiple conditions in a query. All conditions must evaluate to true for the document to be included in the result set.
28. What is the use of the $or operator in MongoDB?
a) To perform a logical AND operation on multiple conditions
b) To perform a logical OR operation on multiple conditions
c) To perform a logical NOT operation on a condition
d) None of the above
Answer: b) To perform a logical OR operation on multiple conditions
Explanation: The $or operator is used in MongoDB to perform a logical OR operation on multiple conditions in a query. At least one condition must evaluate to true for the document to be included in the result set.
29. What is the use of the $not operator in MongoDB?
a) To perform a logical AND operation on multiple conditions
b) To perform a logical OR operation on multiple conditions
c) To perform a logical NOT operation on a condition
d) None of the above
Answer: c) To perform a logical NOT operation on a condition
Explanation: The $not operator is used in MongoDB to perform a logical NOT operation on a condition in a query. The operator negates the specified condition.
30. Which of the following is true about MongoDB?
a) MongoDB is a SQL-based database.
b) MongoDB is a NoSQL database.
c) MongoDB is a relational database.
d) MongoDB is a graph database.
Answer: b) MongoDB is a NoSQL database
Explanation: MongoDB is a NoSQL database, meaning it does not use SQL for querying data. Instead, it uses a flexible document data model with dynamic schemas.
The above MongoDB MCQs cover various aspects of the database system such as data modeling, querying, indexing, and sharding. These MongoDB Multiple Choice Questions provide a good foundation for understanding the fundamentals of MongoDB and its practical applications in the real world. We urge the aspirants to bookmark our Freshersnow portal to regularly receive updates on various technical concept quizzes.