Search Worked Locally but Failed in Production
A search feature worked perfectly on local data but failed in production because matching was case-sensitive in one environment and inconsistent in real records.
Search looked perfect during development, but production users said results were missing unless they typed the exact same casing. Example: Searching for: john did not return: John
The search logic was written with assumptions based on clean local test data. In production, real records had mixed casing: John JOHN joHn The comparison logic was inconsistent, so matches were skipped.
Fix:
Normalize both sides before comparison.
Example:
value.toLowerCase().includes(search.toLowerCase())
For database queries, use a case-insensitive approach that matches your stack properly.
Lesson:
If your feature depends on text matching, always test with dirty real-world data:
- mixed case
- extra spaces
- null values
- unexpected formatting
A feature is not truly working until it survives messy production data.
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