MongoDB MongoDB Query Language and Operators 3

Question 1

What does the $elemMatch operator do when used in a MongoDB query on an array field?

Accepted Answer

Matches documents where at least one array element satisfies all specified conditions

Answer

Returns all elements from the matching array

Answer

Counts the number of matching array elements

Answer

Returns only the matching elements from the array

Question 2

What is the purpose of the $size operator in a MongoDB query?

Accepted Answer

Matches documents where an array field has the specified number of elements

Answer

Returns the byte size of a document

Answer

Sets a maximum size for query results

Answer

Compares the sizes of two array fields

Question 3

Which MongoDB query operator matches values that are greater than or equal to a specified value?

Accepted Answer

$gte

Answer

$gt

Answer

$ge

Answer

$goe

Question 4

What does the $not operator do in a MongoDB query?

Accepted Answer

Inverts the effect of a single query expression

Answer

Returns documents that don't match any query expression

Answer

Checks if a field value is not null

Answer

Excludes a field from the projection

Question 5

Which operator performs a modulo operation on the value of a field in a MongoDB query?

Accepted Answer

$mod

Answer

$divide

Answer

$remainder

Answer

$modulo

Question 6

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

Accepted Answer

.limit(n)

Answer

.max(n)

Answer

.top(n)

Answer

.restrict(n)

Question 7

Which MongoDB query operator matches documents where a field value falls within a specified range using two boundary values?

Accepted Answer

Combining $gte and $lte operators

Answer

$between

Answer

$range

Answer

$within