>If an item is modified outside of a transaction while the transaction is in progress, the transaction is canceled and an exception is thrown You are still res

>If an item is modified outside of a transaction while the transaction is in progress, the transaction is canceled and an exception is thrown You are still responsible to implements a Queue or a Lock on the Items you want to mutate. That said this is a huge milestone for DynamoDB, we can now safely mutate multiples items while remaining ACID.