DynamoDB vs MongoDB vs Cassandra - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a DynamoDB table with a primary key named 'UserId'.

DynamoDB

table = dynamodb.create_table(
    TableName='Users',
    KeySchema=[{'AttributeName': '[1]', 'KeyType': 'HASH'}],
    AttributeDefinitions=[{'AttributeName': 'UserId', 'AttributeType': 'S'}],
    ProvisionedThroughput={'ReadCapacityUnits': 5, 'WriteCapacityUnits': 5}
)

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

AUsername

BUserId

CEmail

DId

Attempts:

3 left

💡 Hint

Common Mistakes

Using a different attribute name than defined in AttributeDefinitions.

The primary key attribute name must match the one defined in AttributeDefinitions. Here, 'UserId' is the correct primary key.

2fill in blank

medium

Complete the code to insert an item into a DynamoDB table named 'Users'.

DynamoDB

table.put_item(Item={'UserId': '123', 'Name': '[1]'})

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

ABob

BAlice

CCharlie

DDavid

Attempts:

3 left

💡 Hint

Common Mistakes

Using a number or invalid type for the 'Name' attribute.

The code inserts an item with 'UserId' 123 and 'Name' 'Bob'. The blank is for the name value.

3fill in blank

hard

Fix the error in the query to get an item by 'UserId' from DynamoDB.

DynamoDB

response = table.get_item(Key={'[1]': '123'})

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

AUserID

BuserId

CUserId

Duserid

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect casing for the key attribute name.

The key name is case sensitive and must exactly match the primary key attribute name 'UserId'.

4fill in blank

hard

Fill both blanks to write a MongoDB query that finds documents where 'age' is greater than 25.

DynamoDB

db.collection.find({ 'age': { '[1]': [2] } })

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

A$gt

B$lt

C25

D30

Attempts:

3 left

💡 Hint

Common Mistakes

Using '$lt' instead of '$gt'.

Using wrong comparison value.

The MongoDB operator for 'greater than' is '$gt'. The value to compare is 25.

5fill in blank

hard

Fill all three blanks to write a Cassandra CQL query that selects 'name' and 'email' from 'users' where 'id' equals 10.

DynamoDB

SELECT [1], [2] FROM users WHERE [3] = 10;

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

Aname

Bemail

Cid

Duser_id

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong column names.

Using 'user_id' instead of 'id'.

The query selects 'name' and 'email' columns from the 'users' table where 'id' equals 10.