Your question is Handle Late Data in Batch. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
You're working on a batch data pipeline and need a clean way to deal with records that show up after the expected processing window. You want the pipeline to stay correct over time without turning every run into a full reload.
How do you handle late-arriving data in a batch-processing system?