BatchWriteItem in DynamoDB - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is BatchWriteItem in DynamoDB?

BatchWriteItem is an operation that lets you write or delete multiple items in one or more tables in a single request. It helps save time by grouping many writes together.

beginner

How many items can you write or delete in a single BatchWriteItem request?

You can write or delete up to 25 items per BatchWriteItem request, with a total request size limit of 16 MB.

intermediate

What happens if some items in a BatchWriteItem request fail to process?

DynamoDB returns the unprocessed items in the response. You can retry those unprocessed items until all are successfully written or deleted.

intermediate

Can BatchWriteItem update existing items in DynamoDB?

No, BatchWriteItem can only put (create or replace) or delete items. It cannot update attributes of existing items partially.

beginner

Why might you use BatchWriteItem instead of multiple individual write requests?

BatchWriteItem reduces the number of network calls and can improve performance and efficiency when writing or deleting many items at once.

What is the maximum number of items you can write or delete in one BatchWriteItem request?

A 25

B 50

C 100

D 10

BatchWriteItem supports up to 25 items per request.

Which of the following operations can BatchWriteItem perform?

A Put and Delete items

B Update item attributes

C Query items

D Scan tables

BatchWriteItem can only put (create or replace) and delete items, not update or query.

If some items fail in a BatchWriteItem request, what does DynamoDB return?

A Partial success without details

B An error and no data

C All items processed successfully

D Unprocessed items to retry

DynamoDB returns unprocessed items so you can retry them.

Why is BatchWriteItem more efficient than multiple single writes?

A It updates items faster

B It scans tables automatically

C It reduces network calls

D It encrypts data

BatchWriteItem groups writes to reduce network overhead.

Which size limit applies to a BatchWriteItem request?

A 1 MB per item

B 16 MB total request size

C 100 MB total request size

D No size limit

BatchWriteItem requests have a 16 MB total size limit.

Explain how BatchWriteItem works and when you would use it.

Think about saving time by grouping writes.

Describe the limitations of BatchWriteItem compared to other DynamoDB write operations.

Focus on what BatchWriteItem cannot do.