Alarm
Defines an action to write to the Amazon DynamoDB table that you created. The default action payload contains all attribute-value pairs that have the information about the alarm model instance and the event that triggered the action. You can also customize the payload. A separate column of the DynamoDB table receives one attribute-value pair in the payload that you specify. You can use expressions for parameters that are strings. For more information, see Expressions in the AWS IoT Events Developer Guide.