CSV Header Handling: Missing Headers and Duplicates
Fix CSV header problems: missing first rows, duplicate column names, whitespace, and BOM characters that break parsers silently.
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Tags: data, csv, parsing
CSV Header Handling: Missing Headers, Duplicates, and Mapping Fields Headers are the skeleton of a CSV file. When they're clean, the rest of the conversion is straightforward. When they're missing, duplicated, or inconsistently formatted, they cause silent data corruption and hard-to-debug downstream failures. This guide covers every common header problem — and the exact code to fix each one. --- When Headers Are Missing A CSV without a header row looks like this: If you parse this with header detection on, the first data row becomes the header — and you lose a record silently. Detecting missing headers (heuristic) There's no foolproof way to detect missing headers, but this heuristic catches most cases: Providing headers externally When you know there's no header row, provide field names…
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