dynamoDB Transactions

Question 1

What are the transaction operations provided by DynamoDB?

Answer 1

DynamoDB provides two transaction operations: TransactWriteItems and TransactGetItems.

Question 2

What is the purpose of the TransactWriteItems operation?

Answer 2

allows grouping of 100 write actions into a single transaction, including :
* PutItem
* UpdateItem
* DeleteItem
* ConditionalCheck

Question 3

What does the TransactGetItems operation contain?

Answer 3

• contains a read set, with one or more GetItem operations.
• can contain up to 100 unique GetItems or 4MB of data, including conditions.

Question 4

What is the atomicity principle in DynamoDB transactions?

Answer 4

The atomicity principle states that transactions are atomic, meaning everything either succeeds or the transaction fails.

Question 5

What is the cost implication of using transactions in DynamoDB?

Answer 5

Transactions are two times more expensive than regular reads/writes because DynamoDB needs to perform two underlying reads/writes of every item, one to prepare the transaction and one to commit the transaction.