Learn MongoDB MCQs

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

What is the purpose of the `$addFields` stage in MongoDB aggregation?

1) To add new fields to documents

2) To remove fields from documents

3) To rename fields

4) To filter documents

Answer : Option 1

Which operator is used to perform a string comparison in MongoDB?

1) $regex

2) $match

3) $equals

4) $stringCompare

Answer : Option 1

What does the command `db.collection_name.updateMany({field: value}, {$set: {field2: newValue}})` do?

1) Updates field2 in all matching documents

2) Deletes all matching documents

3) Finds documents

4) Inserts new documents

Answer : Option 1

What is the default write concern in MongoDB?

1) 1

2) 0

3) majority

4) all

Answer : Option 1

Which command is used to check the current status of a replica set?

1) rs.status()

2) db.replicaSet.status()

3) show replica set

4) db.getStatus()

Answer : Option 1

What is the command to find documents with a specific field value in MongoDB?

1) db.collection_name.find({field: value})

2) db.collection_name.query({field: value})

3) db.collection_name.findByField(value)

4) db.collection_name.search({field: value})

Answer : Option 1

What does the command `db.collection_name.distinct(field)` return?

1) Distinct values of the specified field

2) Total count of documents

3) Documents matching the field

4) All values of the specified field

Answer : Option 1

Which operator is used to match documents with array elements in MongoDB?

1) $elemMatch

2) $arrayIncludes

3) $in

4) $arrayMatch

Answer : Option 1

What is the main purpose of the `db.collection_name.aggregate()` method?

1) To perform complex queries on collections

2) To find documents

3) To update documents

4) To delete documents

Answer : Option 1

Which command is used to count the number of documents in a collection?

1) db.collection_name.count()

2) db.collection_name.size()

3) db.collection_name.countDocuments()

4) db.collection_name.getCount()

Answer : Option 3