Batch limits and retries in DynamoDB - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to specify the maximum number of items allowed in a single batch write request.

DynamoDB

max_items = [1]

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

A25

B50

C100

D10

Attempts:

3 left

💡 Hint

Common Mistakes

Using a number higher than 25 causes the batch request to fail.

Confusing batch write limits with batch get limits.

The maximum number of items allowed in a single DynamoDB batch write request is 25.

2fill in blank

medium

Complete the code to retry unprocessed items after a batch write operation.

DynamoDB

if response.get('UnprocessedItems'):
    retry_items = response['[1]']

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

AProcessedItems

BUnprocessedItems

CItems

DFailedItems

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'ProcessedItems' which contains items already handled.

Assuming all items are processed without checking this key.

UnprocessedItems contains the items that DynamoDB did not process in the batch write and need to be retried.

3fill in blank

hard

Fix the error in the code to correctly handle batch write retries with exponential backoff.

DynamoDB

import time

retry_count = 0
while retry_count < 5:
    response = client.batch_write_item(RequestItems=batch)
    unprocessed = response.get('UnprocessedItems')
    if not unprocessed:
        break
    batch = unprocessed
    time.sleep([1])
    retry_count += 1

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Aretry_count

Bretry_count * 2

C5

D2 ** retry_count

Attempts:

3 left

💡 Hint

Common Mistakes

Using a constant or linear wait time causes inefficient retries.

Not increasing wait time can lead to repeated throttling.

Using exponential backoff with 2 ** retry_count seconds helps avoid throttling by increasing wait time after each retry.

4fill in blank

hard

Fill both blanks to create a batch write request with a limit and handle unprocessed items.

DynamoDB

batch_items = items[:[1]]
response = client.batch_write_item(RequestItems=[2])

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A25

B{'MyTable': batch_items}

C50

D{'TableName': batch_items}

Attempts:

3 left

💡 Hint

Common Mistakes

Using more than 25 items in a batch write.

Incorrect dictionary key for RequestItems.

The batch write limit is 25 items, and the request must be a dictionary with the table name as the key.

5fill in blank

hard

Fill all three blanks to implement a retry loop with batch write, exponential backoff, and unprocessed items handling.

DynamoDB

max_retries = [1]
retry = 0
while retry < max_retries:
    response = client.batch_write_item(RequestItems=[2])
    unprocessed = response.get('UnprocessedItems')
    if not unprocessed:
        break
    [3](2 ** retry)
    retry += 1

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

A5

B{'OrdersTable': batch}

Ctime.sleep

Dclient.batch_write_item

Attempts:

3 left

💡 Hint

Common Mistakes

Not using exponential backoff in retries.

Passing incorrect structure to RequestItems.

Forgetting to sleep between retries.

Set max retries to 5, pass the batch dictionary with table name, and use time.sleep for exponential backoff.