Loading section...

Late-Arriving Facts: Inserting Into Closed Partitions

After you identify the late-arriving fact scenario, the interviewer will ask: 'Show me how your pipeline handles it.' This is where candidates who have only read about late data stall, and candidates who have operated it in production accelerate. The answer involves partition management, aggregate recomputation, and a cascade strategy. Three Strategies: Know All Three, Recommend One The Cascade Problem Interviewers Probe Narrate the cascade: 'I insert the late fact into the March 15 partition. But the daily revenue aggregate for March 15 was already computed as $10M. It is now stale. The monthly aggregate is stale. The dashboard tile is stale. I must mark affected aggregate partitions for recomputation, recompute them, and invalidate dashboard caches. Without this cascade, the base data is