MongoDB MongoDB CRUD Operations 2

Question 1

Which query operator selects documents where the field value is within a specified array?

Accepted Answer

$in

Answer

$in matches documents where the field's value equals any value in the provided array.

Question 2

What does the $push operator do in MongoDB?

Accepted Answer

Appends a value to an array field

Answer

$push appends a specified value to an array field, creating the array if it does not exist.

Question 3

Which method is used to retrieve all documents matching a query in MongoDB?

Accepted Answer

find()

Answer

find() returns a cursor to all documents matching the query filter, or all documents if no filter is provided.

Question 4

How do you limit the number of documents returned by a query in MongoDB?

Accepted Answer

find().limit(5)

Answer

The limit() cursor method restricts the number of documents returned to the specified count.

Question 5

What operator is used to match documents where a field value is NOT equal to a specified value?

Accepted Answer

$ne

Answer

$ne (not equal) selects documents where the field value is not equal to the specified value, including documents without that field.

MongoDB Practice Test