Event ordering, checkpoints, and replays
In the previous sections, we covered some basic topics of Azure Stream Analytics: how to configure inputs and outputs, querying data, and using the service. In the last part of this chapter, I will show you its more advanced features such as event ordering, checkpoints, and replays, which ensure that events are processed in the exact way you would expect. These topics are, in fact, common subjects in many different messaging solutions, so you will be able to use knowledge from this chapter in other projects as well.
Event ordering
There are two concepts of events when it comes to their ordering, as follows:
- Application (or event) time
- Arrival time
There is a clear distinction between them, as noted here:
- Application time: This is a timestamp when an event was generated on the client (or application) side. It tells you exactly when it occurred.
- Arrival time: ...