JSON tree structure in Firebase - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a root node in a Firebase JSON tree.

Firebase

{
  "root": [1]
}

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

A"rootValue"

B"data"

C"value"

D"node"

Attempts:

3 left

💡 Hint

Common Mistakes

Using an empty string as the root value

Using invalid JSON syntax like missing quotes

The root node must have a valid string value. "rootValue" is a clear root node value.

2fill in blank

medium

Complete the code to add a child node named 'users' under the root.

Firebase

{
  "root": {
    [1]: {}
  }
}

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

A"accounts"

B"users"

C"clients"

D"members"

Attempts:

3 left

💡 Hint

Common Mistakes

Using a different child node name

Missing quotes around the key

The child node should be named 'users' as specified.

3fill in blank

hard

Fix the error in the JSON tree by completing the missing key for a user ID.

Firebase

{
  "root": {
    "users": {
      [1]: {
        "name": "Alice"
      }
    }
  }
}

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

A"name"

Buser1

C"user1"

D"id"

Attempts:

3 left

💡 Hint

Common Mistakes

Using unquoted keys which is invalid JSON

Using wrong key names like 'name' or 'id' instead of user ID

User IDs must be strings in quotes. "user1" is the correct key format.

4fill in blank

hard

Fill both blanks to add two users with their names under 'users'.

Firebase

{
  "root": {
    "users": {
      [1]: {"name": "Bob"},
      [2]: {"name": "Carol"}
    }
  }
}

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

A"user1"

B"user2"

C"user3"

D"user4"

Attempts:

3 left

💡 Hint

Common Mistakes

Using duplicate keys

Using keys without quotes

Use unique user IDs as keys for each user node.

5fill in blank

hard

Fill all three blanks to add a nested address object for user1.

Firebase

{
  "root": {
    "users": {
      "user1": {
        "name": "Dave",
        "address": {
          "street": [1],
          "city": [2],
          "zip": [3]
        }
      }
    }
  }
}

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

A"123 Main St"

B"Springfield"

C"12345"

D"Unknown"

Attempts:

3 left

💡 Hint

Common Mistakes

Missing quotes around string values

Using numeric values without quotes for zip

Address fields must be strings representing street, city, and zip code.