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How would you implement a sliding window aggregation in Spark Structured Streaming?

Spark/Big Datahard0.6 min readPremium
Frequency
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Asked at 2 companies
Category
452
questions in Spark/Big Data
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88E|81M|283H
in this category
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1,863
across 7 categories
Asked at these companies
Fragma Data SystemsSwiggy
Key Concepts Tested
sparkwindow
Expert AnswerPremium
123 wordsInterview-ready
Sliding window: window(timeColumn, windowDuration, slideDuration) where slideDuration < windowDuration creates overlapping windows. Example: df.withWatermark("event_time", "10 minutes").groupBy(window(col("event_time"), "1 hour", "10 minutes"), col("user_id")).count(). **Why watermark**: Late data would grow state unbounded; watermark drops events older than (max_event_time - delay) and allows state cleanup....
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