$not operator behavior in MongoDB - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to find documents where the field 'age' is NOT equal to 30.

MongoDB

db.collection.find({ age: { $not: { $eq: [1] } } })

Drag options to blanks, or click blank then click option'

A25

Btrue

C30

Dnull

Attempts:

3 left

💡 Hint

Common Mistakes

Using $not without a condition inside, like { $not: 30 } which is invalid.

Confusing $not with $ne (not equal).

The $not operator negates the condition inside it. Here, { $eq: 30 } means age equals 30, so $not finds ages not equal to 30.

2fill in blank

medium

Complete the code to find documents where the 'status' field does NOT start with the letter 'A'.

MongoDB

db.collection.find({ status: { $not: { $regex: /^[1]/ } } })

Drag options to blanks, or click blank then click option'

AZ

BA

CB

Da

Attempts:

3 left

💡 Hint

Common Mistakes

Using lowercase 'a' when the data is uppercase 'A' (case sensitive).

Not using the caret ^ to specify start of string.

The regular expression /^A/ matches strings starting with 'A'. Using $not negates this, so it finds strings not starting with 'A'.

3fill in blank

hard

Fix the error in the query to find documents where 'score' is NOT greater than 50.

MongoDB

db.collection.find({ score: { $not: { $gt: [1] } } })

Drag options to blanks, or click blank then click option'

A60

B40

C30

D50

Attempts:

3 left

💡 Hint

Common Mistakes

Using a number other than 50 inside $gt changes the meaning.

Trying to use $not: 50 directly, which is invalid.

The query uses $gt: 50 to find scores greater than 50. $not negates this, so it finds scores less than or equal to 50.

4fill in blank

hard

Fill both blanks to find documents where 'category' is NOT 'electronics' and 'price' is NOT less than 100.

MongoDB

db.collection.find({ category: { $not: { $eq: "[1]" } }, price: { $not: { $lt: [2] } } })

Drag options to blanks, or click blank then click option'

Aelectronics

Bbooks

C100

D50

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up the price threshold value.

Using $ne instead of $not with $eq or $lt.

The query excludes documents where category equals 'electronics' and price is less than 100 by negating those conditions with $not.

5fill in blank

hard

Fill all three blanks to find documents where the 'name' field does NOT contain 'Pro', 'rating' is NOT equal to 5, and 'stock' is NOT less than 10.

MongoDB

db.collection.find({ name: { $not: { $regex: [1] } }, rating: { $not: { $eq: [2] } }, stock: { $not: { $lt: [3] } } })

Drag options to blanks, or click blank then click option'

A/Pro/

B5

C10

D/Pro/i

Attempts:

3 left

💡 Hint

Common Mistakes

Using case-sensitive regex when case-insensitive is needed.

Mixing up the numeric values for rating and stock.

The regex /Pro/i matches 'Pro' case-insensitively. Using $not excludes names containing 'Pro'. Similarly, $not excludes ratings equal to 5 and stock less than 10.