Topic

CSV

The format everyone exports and nobody specifies. Delimiters, quoting, encodings and loading it into a database intact.

CSV

Converting CSV to JSON in Node With a Few Lines of Code

Convert a CSV to JSON or NDJSON in Node with csv-parse, keep ZIP codes as text, and stream 2,000,000 rows at 120 MB instead of 1.6 GB.

8 min read

CSV

Why Splitting CSV by Comma in JavaScript Goes Wrong

line.split(',') breaks on quoted commas, quotes, line breaks and CRLF. See the failures, why the regex fix is slow, and a 30 line parser that works.

7 min read

CSV

Generating a CSV Download From JavaScript in the Browser

Build a CSV string, wrap it in a Blob and trigger a download with an object URL. Covers escaping, the Excel BOM, formula guards and how 1,000,000 rows behave.

9 min read

CSV

Parsing CSV in the Browser With Papa Parse Without Blocking

Parse an uploaded CSV in the browser with Papa Parse: typing traps, error objects, encodings, and chunks and workers measured on 500,000 rows.

11 min read

CSV

Using csv parse in Node for Large Files Without Surprises

The csv-parse options that matter on big files in Node: columns, cast, on_record, relax_quotes and max_record_size, timed on 2,000,000 rows.

8 min read

CSV

Reading a CSV File in Node With Streams and Backpressure

Read a large CSV in Node with fs.createReadStream and csv-parse, filter with pipeline, stop early, and handle errors, BOMs and Windows-1252 files.

9 min read

Parsing CSV in JavaScript and Node Without Surprises

A tested guide to CSV in JavaScript: csv-parse, Papa Parse and a hand-written parser timed on 2,000,000 rows, plus streams, types, uploads and downloads.

20 min read

CSV

Splitting a CSV by Column Value Into Separate Files

Split a CSV into one file per column value with awk, qsv, Miller or DuckDB, keep the header in every file, check the counts and avoid unsafe file names.

9 min read

CSV

Removing Duplicate Rows From a CSV With Shell Tools

Remove duplicate CSV rows with sort -u, awk, qsv and Miller. See what each does to the header and the order, which row it keeps, and why awk drops a good row.

9 min read

CSV

Sorting a CSV File by Column in the Terminal Correctly

Sort a CSV by column from the shell without losing the header or reading text as numbers. Compare sort, qsv, Miller, csvsort and DuckDB on 2,000,000 rows.

9 min read

CSV

Counting Rows and Unique Values in a CSV From the Shell

Count records and distinct values in a CSV from the shell with wc, sort, uniq, qsv and Miller, and see why wc -l and messy spellings give wrong counts.

7 min read

CSV

Using qsv for Fast CSV Statistics and Slicing of Big Files

qsv counts, profiles, searches, slices and sorts CSV files in fractions of a second. See count, stats, frequency, slice and index run on 2,000,000 rows.

9 min read

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