title: AWS DynamoDB trigger invocation speed and synchronization
body: <p>Do triggers on DynamoDB tables have some sort of internal synchronization to keep everything in the order it is supposed to be? 
  Example: my trigger batch size is 1 and it's configured to always start reading from the latest entry. Two entries are made to the DB at one millisecond apart (or at the same time). I don't know the time it takes for the trigger and lambda function to be invoked but let's say for argument's sake it's longer than the time between DB entries (>1ms). Can I be sure that both lambda invocations don't receive the data from the second DB entry? </p>