Learn MongoDB MCQs

Prepare MongoDB MCQs (Multiple choice Questions) for exam and job interviews.

What is the purpose of the `$out` stage in aggregation?

1) Writes the results to a specified collection

2) Joins two collections

3) Filters documents

4) Groups documents

Answer : Option 1

Which command is used to drop a collection?

1) db.collection_name.drop()

2) db.collection_name.remove()

3) db.deleteCollection()

4) db.collection_name.delete()

Answer : Option 1

What does the command `db.collection_name.find({field: {$not: {$gt: value}}})` do?

1) Finds documents where field is not greater than value

2) Finds documents where field is greater than value

3) Finds documents where field is null

4) Finds all documents

Answer : Option 1

What operator is used to filter documents with a specific substring in a string field?

1) $regex

2) $substring

3) $match

4) $contains

Answer : Option 1

Which command is used to remove all documents from a collection?

1) db.collection_name.deleteMany({})

2) db.collection_name.removeAll()

3) db.collection_name.clear()

4) db.collection_name.delete()

Answer : Option 1

What does the `db.collection_name.find().pretty()` command do?

1) Formats the output of documents for readability

2) Finds all documents

3) Finds documents matching a query

4) Deletes documents

Answer : Option 1

Which operator is used to filter documents with a specific value in an array?

1) $elemMatch

2) $in

3) $contains

4) $any

Answer : Option 1

What command is used to view the current database in use?

1) db

2) db.current()

3) db.getCurrentDatabase()

4) db.showCurrent()

Answer : Option 1

What does the command `db.collection_name.updateOne({field: value}, {$inc: {field2: 1}})` do?

1) Increments field2 by 1 in the first matching document

2) Updates field2 to 1 in the first matching document

3) Deletes the document

4) Inserts a new document

Answer : Option 1

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

1) use database_name

2) db.createDatabase("database_name")

3) db.newDatabase("database_name")

4) db.create("database_name")

Answer : Option 1