A MERGE pipeline keys dim_customer on email
A medium Pipeline Design mock interview question on DataDriven. Practice with AI-powered feedback, real code execution, and a hire/no-hire decision.
- Domain
- Pipeline Design
- Difficulty
- medium
Interview Prompt
A MERGE pipeline keys dim_customer on email. A customer updated their email, the MERGE missed the match, and a duplicate row was inserted; historical lineage broke because the natural key changed. The section frames the fix in two halves: a stable surrogate key and a uniqueness assertion at write time. Apply both halves on the canvas; warehouses do not enforce primary keys for you.
How This Interview Works
- Read the vague prompt (just like a real interview)
- Ask clarifying questions to the AI interviewer
- Write your pipeline design solution with real code execution
- Get instant feedback and a hire/no-hire decision