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PYSPARK • LESSON 98

Inclusion Checking with Semi Join

How do we filter customer profiles for active buyers without appending duplicate order columns using left_semi?

Advanced2 Minutes510 XP
🤔 THE QUESTION

How do we filter customer profiles for active buyers without appending duplicate order columns using left_semi?

💡 WHAT IS IT?

left_semi filters the left table to rows matching the right table without bringing in right-table columns.

🎯 WHAT IS IT USED FOR?

High-performance set existence checks without row multiplication or unnecessary schema widening.

💻 EXAMPLE
active_buyers = customers.join(recent_orders, "customer_id", "left_semi")

🎯 Mission Objectives

Practice typing production-grade PySpark code for Inclusion Checking with Semi Join.

  • Execute left_semi join
  • Filter matching left-side entities
  • Prevent schema widening and row multiplication