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Code Keys/PySpark Academy/Module 35/Lesson 293
PYSPARK • LESSON 293

Capstone Part 3: CDC Natural Key Deduplication

How can we ensure exactly one latest record per event_id is retained during Change Data Capture ingestion?

Production⏱ 3 Minutes⭐ 820 XP
🤔 THE QUESTION

How can we ensure exactly one latest record per event_id is retained during Change Data Capture ingestion?

💡 WHAT IS IT?

Window row_number() over event_id ordered by event_timestamp desc isolates the most up-to-date state snapshot.

🎯 WHAT IS IT USED FOR?

Eliminating duplicate upstream event transmissions and ensuring idempotent state replication.

💻 EXAMPLE
w = Window.partitionBy("event_id").orderBy(col("event_timestamp").desc())
df_deduped = df_clean.withColumn("rn", row_number().over(w)).filter(col("rn") == 1).drop("rn")

🎯 Mission Objectives

Practice typing production-grade PySpark code for Capstone Part 3: CDC Natural Key Deduplication.

  • ✓ CDC row_number() deduplication
  • ✓ Latest state snapshot selection
  • ✓ Idempotent event processing
🚀 Start Mission
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