Hot partition prevention in DynamoDB - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to specify the partition key attribute in a DynamoDB table creation.

DynamoDB

KeySchema=[{'AttributeName': '[1]', 'KeyType': 'HASH'}]

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

ARegion

BTimestamp

CSortKey

DUserId

Attempts:

3 left

💡 Hint

Common Mistakes

Using a timestamp as partition key can cause hot partitions.

Using a sort key as partition key is incorrect.

The partition key is the primary key attribute used to distribute data across partitions. 'UserId' is a common choice to avoid hot partitions.

2fill in blank

medium

Complete the code to add a sort key to the DynamoDB table schema.

DynamoDB

KeySchema=[{'AttributeName': 'UserId', 'KeyType': 'HASH'}, {'AttributeName': '[1]', 'KeyType': 'RANGE'}]

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

ATimestamp

BUserId

CRegion

DStatus

Attempts:

3 left

💡 Hint

Common Mistakes

Using the same attribute as partition and sort key.

Choosing an attribute with low cardinality as sort key.

The sort key allows sorting items with the same partition key. 'Timestamp' is often used to order events.

3fill in blank

hard

Fix the error in the partition key design to prevent hot partitions by using a composite key pattern.

DynamoDB

PartitionKey = userId + '[1]'

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AUserId

BRegion

CStatus

DTimestamp

Attempts:

3 left

💡 Hint

Common Mistakes

Concatenating timestamp can cause uneven distribution if timestamps cluster.

Using the same attribute twice in the key.

Adding 'Region' to the partition key helps distribute traffic across partitions, reducing hot partition risk.

4fill in blank

hard

Fill both blanks to create a partition key that includes a user ID and a hashed value to spread load evenly.

DynamoDB

PartitionKey = '[1]' + '#' + hash([2])

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

AUserId

BTimestamp

CRegion

DStatus

Attempts:

3 left

💡 Hint

Common Mistakes

Hashing the user ID instead of timestamp.

Using attributes with low variability.

Combining 'UserId' with a hash of 'Timestamp' helps distribute writes across partitions by adding randomness.

5fill in blank

hard

Fill all three blanks to create a DynamoDB item with a partition key, sort key, and an attribute to prevent hot partitions.

DynamoDB

Item = {'PartitionKey': [1], 'SortKey': [2], 'Region': [3]

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

A'UserId#' + str(hash(userId))

BTimestamp

C'us-east-1'

D'Status'

Attempts:

3 left

💡 Hint

Common Mistakes

Using plain user ID without hashing for partition key.

Using a non-time attribute as sort key.

Not including region or similar attribute for distribution.

The partition key combines user ID with a hash to spread load. The sort key is timestamp for ordering. The region attribute helps identify data location and can be used for further distribution.