P28Data CleaningIntermediateImplement14 min
Clean Mixed Date Formats
Parse a column containing multiple date formats without silently swapping day and month.
#dates#parsing#data-quality
Scenario
A vendor export mixes 2026-03-04, 04/03/2026, and invalid text in one signup_date column.
Problem statement
Design a parsing and validation workflow that makes ambiguity visible.
Your Task
- Preserve the raw value.
- Parse with explicit rules where the source format is known.
- Measure parsing failures and investigate ambiguous records.
Related Concepts
Datetime parsingSource systemsData audits
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