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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 readPremium
Frequency
Low
Asked at 1 company
Category
487
questions in SQL
Difficulty Split
130E|271M|86H
in this category
Total Bank
1,863
across 7 categories
Asked at these companies
Amazon
Expert AnswerPremium
92 wordsInterview-ready
**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....
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