Time Semantics in Stream Processing
Understand event time, processing time, and ingestion time, and why choosing the right time semantic is critical for correct stream results.
Why Time Matters
In stream processing, when an event happened is often more important than when you processed it.
Choosing the wrong notion of time leads to incorrect counts, broken windows, and misleading analytics.
Event Time
Event time is the timestamp embedded in the event itself — when it actually occurred at the source.
- A purchase made at 14:03 carries 14:03 regardless of network delays.
- It produces deterministic, replayable results.
All lessons in this course
- What is Stream Processing?
- Batch vs. Stream Processing
- Stream Processing Paradigms
- Time Semantics in Stream Processing