Index intersection behavior in MongoDB - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to find documents where age is 25 using an index.

MongoDB

db.users.find({ age: [1] })

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

A"25"

B{ $eq: 25 }

C25

D{ age: 25 }

Attempts:

3 left

💡 Hint

Common Mistakes

Using quotes around numbers causes type mismatch.

Using nested objects incorrectly in the query.

The query needs the value 25 directly to match the age field.

2fill in blank

medium

Complete the query to find documents where age is 25 and status is 'A' using index intersection.

MongoDB

db.users.find({ age: 25, status: [1] })

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

A{ status: "A" }

B"A"

C{ $eq: "A" }

DA

Attempts:

3 left

💡 Hint

Common Mistakes

Not quoting string values causes errors.

Using nested objects unnecessarily.

The status value must be a string, so it needs quotes.

3fill in blank

hard

Fix the error in the query to use index intersection for age and status.

MongoDB

db.users.find({ age: [1], status: "A" })

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

A"25"

B{ age: 25 }

C{ $eq: 25 }

D25

Attempts:

3 left

💡 Hint

Common Mistakes

Using string '25' instead of number 25.

Using nested objects incorrectly.

Age should be a number, not a string or nested object.

4fill in blank

hard

Fill both blanks to create a query that uses index intersection for age and status.

MongoDB

db.users.find({ age: [1], status: [2] })

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

A25

B"A"

C30

D"B"

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up numbers and strings.

Using wrong values for age or status.

The query filters age by 25 (number) and status by "A" (string).

5fill in blank

hard

Fill all three blanks to create a query that uses index intersection for age, status, and score.

MongoDB

db.users.find({ age: [1], status: [2], score: [3] })

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

A25

B"A"

C85

D"B"

Attempts:

3 left

💡 Hint

Common Mistakes

Quoting numbers or not quoting strings.

Using wrong values for fields.

The query filters age by 25 (number), status by "A" (string), and score by 85 (number).