Why advanced updates matter in MongoDB - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to update the age of a user named 'Alice' to 30.

MongoDB

db.users.updateOne({name: 'Alice'}, {$set: {age: [1])

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

A25

B30

C35

D40

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong age value.

Forgetting to use $set operator.

The $set operator updates the specified field. Here, we set age to 30.

2fill in blank

medium

Complete the code to increment the score of a player named 'Bob' by 10.

MongoDB

db.players.updateOne({name: 'Bob'}, {$inc: {score: [1])

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

A5

B20

C10

D15

Attempts:

3 left

💡 Hint

Common Mistakes

Using $set instead of $inc.

Using wrong increment value.

The $inc operator increases the value of the field by the specified amount. Here, we increment score by 10.

3fill in blank

hard

Fix the error in the update code to add a new tag 'urgent' to the tags array for task with id 123.

MongoDB

db.tasks.updateOne({_id: 123}, {$push: {tags: [1])

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

A'urgent'

Burgent

C{urgent}

D[urgent]

Attempts:

3 left

💡 Hint

Common Mistakes

Not quoting the string value.

Using curly braces or brackets incorrectly.

Strings in MongoDB update queries must be quoted. So, 'urgent' is correct to add the tag.

4fill in blank

hard

Fill both blanks to update the price to 19.99 and set the status to 'available' for product with id 456.

MongoDB

db.products.updateOne({_id: 456}, {$set: {price: [1], status: [2])

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

A19.99

B'available'

C'sold out'

D20.99

Attempts:

3 left

💡 Hint

Common Mistakes

Quoting numbers or not quoting strings.

Using wrong values for price or status.

Price is a number so no quotes needed. Status is a string and must be quoted.

5fill in blank

hard

Fill all three blanks to update the user's email, increment login count by 1, and add 'premium' to roles array for user with username 'jane'.

MongoDB

db.users.updateOne({username: 'jane'}, {$set: {email: [1], $inc: {logins: [2], $push: {roles: [3])

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

A'[e-mail]'

B1

C'premium'

D'[e-mail]'

Attempts:

3 left

💡 Hint

Common Mistakes

Not quoting strings, wrong increment value, or wrong email.

Email is a string and must be quoted. Login increment is numeric. Role added is a string and must be quoted.