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Home/Questions/SQL/Describe a situation where you made a mistake in a data pipeline. How did you identify and fix it?

Describe a situation where you made a mistake in a data pipeline. How did you identify and fix it?

SQLeasy0.5 min read

Reviewed by Aditya Kumar · Last reviewed 2026-03-24

**Situation**: Pipeline bug applied wrong exchange rates to multi-currency transactions for one week. **Task**: Correct data and prevent recurrence. **Action**: Finance spotted discrepancies; traced to pipeline. Found hardcoded rate in UDF. Fix: (1) Corrected UDF to use rate...

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Expert Answer
92 words

Situation: Pipeline bug applied wrong exchange rates to multi-currency transactions for one week. Task: Correct data and prevent recurrence. Action: Finance spotted discrepancies; traced to pipeline. Found hardcoded rate in UDF. Fix: (1) Corrected UDF to use rate lookup table. (2) Identified affected date range. (3) Backfilled with correct rates. (4) Communicated to stakeholders. (5) Added integration test for rate logic. (6) Implemented reconciliation checks. Result: Data corrected in 2 days. Leadership: Took ownership; transparent communication; drove preventive measures. Outcome: Code review mandate; unit tests for business logic; monitoring for rate anomalies.

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Pro Tip

Red Flag: Blaming others or downplaying impact. Pro-Move: Own it; describe detection (who found it), fix (technical), prevention (tests, reconciliation); show blameless post-mortem culture.

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