The Analyst Who Saw the Salary Data
A hard 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
- hard
- Seniority
- L5
Interview Prompt
We run a multi-tenant data lake shared by five business units with very different sensitivity levels, and everything currently sits in one flat store behind a single shared reader role. Two incidents have already leaked one unit's data to another: an analyst read another unit's files directly, and a misconfigured pipeline wrote into the wrong unit's area. Redesign the lake so each unit gets its own isolated store fed by its own write path, and the few pre-approved cross-unit reads (marketing needs only the customer-dimension columns from finance, not the whole store) are served through a governed query engine sitting between the stores and the analysts that hands back just the approved columns, never blanket access to another unit's store.
Summary
Two incidents. One shared lake. The access model was never designed, just assumed.
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