CSV Filter & Deduplicate

Keep rows matching a literal condition, then remove repeated rows or key-column matches.

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About this flow

Extract a useful subset of a CSV or TSV, then keep the first row for each exact duplicate key. Choose a column and literal comparison, review the filtered checkpoint, and download the deduplicated result with optional final spreadsheet formula protection.

Limitations

The first row is the header. Filtering compares literal text; no regular expressions or inferred data types are used.
Duplicate key positions refer to the original column order. Exact comparisons preserve case and whitespace.
Final formula protection preserves complete bounded signed decimal/exponent numbers and adds an apostrophe to formula or control-prefixed expressions. CSV/TSV imports may infer types; import identifier columns as text. Protection OFF retains literal expressions with spreadsheet execution risk.
Input and downstream step admission remain 5 MiB, with a 20 MiB final output ceiling.
Use UTF-8 text with a consistent number of fields per row. Ragged rows and malformed quoting fail before processing; blank physical lines in a multi-column table must be represented as correctly shaped empty records.
A table may contain up to 50,000 data rows, 500 columns and 500,000 cells. Processed files quote every cell and use CRLF record separators.