Data Engineering interview question · Most asked
Scenario: two dashboards show different numbers for the same metric. What do you do?
Summary
Trace both metrics through lineage to their definitions: different filters (cancelled orders, test accounts), grains, time zones or date bases, refresh times, or fan-out bugs. Agree one definition with the business, implement it once in a shared model or semantic layer, and point both dashboards at it.
Longer Answer
Prevent repeats with a single source of truth for key metrics (a metrics/semantic layer or governed marts), documented definitions and reconciliation tests.
Key Points
- Compare definitions via lineage.
- Check filters, grain, time zones and freshness.
- One shared definition.
- Semantic layer or governed marts.
Explanation
What interviewers look for
Root-cause tracing and governance fix.
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