MongoDB MongoDB Query Language and Operators

Question 1

Which MongoDB query operator matches documents where a field value is greater than a specified value?

Accepted Answer

$gt

Answer

$gte

Answer

$lt

Answer

$lte

Question 2

Which operator selects documents where a field value matches any value in a specified array?

Accepted Answer

$in

Answer

$exists

Answer

$all

Answer

$elemMatch

Question 3

What does the $and operator do in a MongoDB query?

Accepted Answer

Returns documents where all conditions are true

Answer

Returns documents matching any one condition

Answer

Negates all conditions in the query

Answer

Combines results from two collections

Question 4

How do you apply a projection in a MongoDB find() query to return only specific fields?

Accepted Answer

db.col.find({filter}, {field: 1})

Answer

db.col.find({filter}, {field: true})

Answer

db.col.find({field: 1})

Answer

db.col.project({field: 1}).find({filter})

Question 5

What does the $ne operator match in a MongoDB query?

Accepted Answer

Documents where the field value is not equal to the specified value

Answer

Documents where the field is null

Answer

Documents where the field does not exist

Answer

Documents where the field is a non-empty string

Question 6

Which operator is used to match documents where an array field contains all of the specified elements?

Accepted Answer

$all

Answer

$in

Answer

$elemMatch

Answer

$size

Question 7

What is the correct MongoDB syntax to sort query results in descending order by a field named 'score'?

Accepted Answer

.sort({score: -1})

Answer

.sort({score: 0})

Answer

.sort({score: 'desc'})

Answer

.sort({score: false})