How MongoDB stores data as documents - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to insert a document into the collection.

MongoDB

db.collection.insertOne({ name: "Alice", age: [1] })

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

Aage

B25

C"25"

Dnull

Attempts:

3 left

💡 Hint

Common Mistakes

Putting numbers inside quotes makes them strings.

Using undefined variables instead of values.

The age field should be a number, so 25 without quotes is correct.

2fill in blank

medium

Complete the code to find all documents where age is greater than 20.

MongoDB

db.collection.find({ age: { [1]: 20 } })

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

A$lt

B$ne

C$eq

D$gt

Attempts:

3 left

💡 Hint

Common Mistakes

Using $lt which means less than.

Using $eq which means equal.

The operator $gt means 'greater than'.

3fill in blank

hard

Fix the error in the query to find documents with name 'Bob'.

MongoDB

db.collection.find({ name: [1] })

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

A"Bob"

B{Bob}

C'Bob'

DBob

Attempts:

3 left

💡 Hint

Common Mistakes

Not using quotes around string values.

Using single quotes which may cause errors in some shells.

String values in MongoDB queries must be in double quotes.

4fill in blank

hard

Fill both blanks to create a document with a nested address field.

MongoDB

db.collection.insertOne({ name: "Eve", address: { [1]: "123 Main St", [2]: "NY" } })

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

Astreet

Bcity

Cstate

Dzip

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up city and state fields.

Using invalid field names.

The nested document has fields 'street' and 'state' for the address.

5fill in blank

hard

Fill all three blanks to query documents where age is less than 30 and city is 'LA'.

MongoDB

db.collection.find({ [1]: { [2]: 30 }, city: [3] })

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

Aage

B$lt

C"LA"

Dcity

Attempts:

3 left

💡 Hint

Common Mistakes

Using $gt instead of $lt.

Not quoting string values.

Mixing up field names.

The query filters documents where age is less than 30 and city equals 'LA'.