Suppose you have a Keen IO collection called "survey-completed" that contains events matching the following pattern:
keen.id: <unique autogenerated id>
keen.timestamp: <autogenerated overridable timestamp>
userId: <hex string for user>
surveyScore: <integer from 1 to 10>
...
How would you create a report of only the most up-to-date satisfaction score for each user that responded to one or more surveys within a given amount of time (such as one week)?