Marketing asks the data team for a very specific list: every registered customer who did not place a single order in October. The relevant tables are catalog.sales.customers, with one row per customer, and catalog.sales.orders, with many rows per order. The engineer wants a single PySpark join call that returns exactly those customers and nothing else. Which join type should the engineer use?
Reveal answer
Correct answer: 'left_anti', which returns the customers whose key has no match among the orders
Reference: https://docs.databricks.com/aws/en/pyspark/reference
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02 — The Myelin Layer · Canonical Discussion
Where the exam tries to trick you — and how those who passed solved it.
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Official Answer (B): 'left_anti', which returns the customers whose key has no match among the orders
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