Sorting by multiple fields in MongoDB - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does sorting by multiple fields mean in MongoDB?

It means arranging documents in order based on more than one field, for example, first by age, then by name.

beginner

How do you specify sorting order for multiple fields in MongoDB?

You provide an object to sort() with field names as keys and 1 for ascending or -1 for descending as values, like { age: 1, name: -1 }.

beginner

What happens if two documents have the same value in the first sorted field?

MongoDB uses the next field in the sort order to decide which document comes first.

intermediate

Write a MongoDB query to sort users first by score descending, then by username ascending.

db.users.find().sort({ score: -1, username: 1 })

beginner

Why is sorting by multiple fields useful in real life?

It helps organize data clearly, like sorting a contact list by last name and then first name, so people with the same last name are grouped and ordered by first name.

In MongoDB, how do you sort documents by two fields, age ascending and name descending?

A sort({ age: 'asc', name: 'desc' })

B sort({ age: -1, name: 1 })

C sort({ age: 1, name: -1 })

D sort(['age', 'name'])

Use 1 for ascending and -1 for descending in the sort object.

What does the number -1 mean in a MongoDB sort object?

A Sort descending

B Sort ascending

C Ignore the field

D Sort randomly

In MongoDB, -1 means descending order.

If two documents have the same value in the first sorted field, what does MongoDB do?

A Deletes one document

B Returns an error

C Leaves them unordered

D Sorts by the next field in the sort object

MongoDB uses the next field to break ties.

Which of these is a valid MongoDB sort command to sort by price ascending and rating descending?

A sort({ price: 1, rating: -1 })

B sort({ price: -1, rating: 1 })

C sort({ price: 'asc', rating: 'desc' })

D sort(price, rating)

Use 1 for ascending and -1 for descending in the sort object.

Why might you want to sort by multiple fields in a database?

A To make data look random

B To organize data clearly when one field alone is not enough

C To delete duplicate data

D To speed up queries

Sorting by multiple fields helps organize data better when one field is not enough.

Explain how to sort documents by multiple fields in MongoDB and why it is useful.

Think about sorting by age then name.

Write a MongoDB query to sort a collection by two fields: first descending by date, then ascending by title.

Use 1 for ascending and -1 for descending.