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qsv is a blazing-fast, composable data-wrangling toolkit for CSV, TSV, SSV, Excel, JSON/JSONL, Parquet and more. 79 commands across five binary variants, and a single binary that fits in your toolbox.
Latest release: 23.0.1 — the "Context is King" release — ~270 commits since 22.0.1, and the theme is context: the surrounding facts that turn a number into a finding. A count of 4,312 says nothing; 4,312 per 100,000 residents says where to look. The headliner is the Data Schematic's deep US Census integration — --geojson auto fetches US boundaries from Census TIGERweb, --denominator census fetches the matching population denominators, and a --locations column of county or city names — not just FIPS codes — resolves with nothing supplied but the CSV. describegpt closes the loop by deriving the denominator and declaring the geography it describes, so a rate map draws without the reader naming either column — and refuses when the denominator is constant or measured over the wrong geography. One new command: readstat converts SAS, Stata & SPSS files to CSV, no licence required. Data Schematics now open with a guided Tour whose audience you choose (--tour-audience "the City Council"), and carry units and money so a tile reads "18.4 °C" or "$192B" rather than a bare float. Underneath: a sustained correctness sweep — a four-batch stats.rs review, count no longer disagreeing with itself on blank lines, and race-free atomic auto-indexing. qsvmcp users only — it no longer ships get, dc: inputs or cloud sources.
Important
Unreleased (after 23.0.1): coming in the next release, with breaking changes. Its x86_64 prebuilts require AVX2 — don't qsv --update on an older CPU (check first). The profile DCAT-US v3 projection switches to canonical unprefixed keys. Some sqlp queries change behavior. moarstats grows to 73 measures (Aggregation & Statistics). Pages mark these changes with the same "Unreleased (after 23.0.1)" label.
Welcome! This wiki is the workflow + discoverability layer for qsv. Use it to learn how the commands fit together and find recipes for real-world tasks. For per-command flag references, follow the deep-links into /docs/help/ — that's the canonical reference.
| Path | When |
|---|---|
| Try it in your browser | You want to evaluate qsv before installing anything |
| Install qsv | You're ready to run it locally |
| Read the Whirlwind Tour | You want a guided 2.7M-row walkthrough |
Then jump to Getting Started for a hands-on tutorial, or Why qsv? for the elevator pitch.
qsv documentation lives on several surfaces. Each has a different job:
| Surface | Job |
|---|---|
README.md |
Project overview, command catalog with legend, install options, feature flags |
/docs/ (canonical reference) |
The source of truth: PERFORMANCE.md, BENCHMARKS.md, ENVIRONMENT_VARIABLES.md, STATS_DEFINITIONS.md, Validate.md, Fetch.md, Describegpt.md, INTERPRETERS.md, plus the whirlwind tour
|
/docs/help/ |
Per-command help — flags, arguments, examples |
| This wiki | Workflow & discoverability: getting started, cookbook recipes, command-reference category guides, tuning, integrations, troubleshooting |
| 100.dathere.com | Interactive lessons & exercises (WIP) |
| Discussions | Q&A, FAQ, announcements, ideas |
 |
LLM-generated Wiki that crawls the codebase once a week, that you can chat with! |
Every wiki page has a Tier badge — Beginner, Intermediate, or Advanced. See the Tier Legend for what each tier assumes.
Installation · Getting Started · Why qsv? · Command Reference (index) · Cookbook · Troubleshooting · FAQ · Glossary · External Resources · qsv pro
Binary Variants · Transform & Reshape · Aggregation & Statistics · Joins & Set Ops · Validation & Schema · Conversion & I/O · Geospatial · HTTP & Web · Indexing, Compression & Diff · AI & Documentation · Comparison vs others · Integrations · Claude Cowork Plugin · MCP Server
SQL & Polars · Scripting (Luau / Python) · Performance Tuning · Environment Variables · Stats Cache & Caching · Lookup Tables · Contributing to the Wiki
Examples in this wiki reach for a small set of datasets repeatedly, so you build mental models:
-
wcp.csv— World Cities Population, 2.7M rows / 124 MB. Used in Getting Started and many command-reference examples. Available infiles/wcp.zip. - NYC 311 Service Requests — public dataset, available as a 1M-row sample and a full 16 GB / 27M-row export. Used in Validation, SQL & Polars, Geographic Enrichment, Larger-than-RAM.
-
Boston 311 — small (100 rows) and in many compression formats (
.csv,.gz,.zst,.parquet). Used in Clean & Normalize and conversion demos. - Allegheny County property sales — mid-size, already indexed. Used in Build a Data Pipeline and Stats → Insights.
-
NOAA GHCN-Daily — weather time-series, fetched via
qsv fetch. Used in Fetch & Cache and Multi-table Joins (asof joins). -
GitHub stargazers — qsv's own stars, fetched via
qsv fetch. Used in HTTP & Web demos.
No install required: visit qsv.dathere.com to try qsv against a sample CSV right now.
- "Have we achieved ACI?" series: 1 · 2 · 3
- NYC SOD 2026 · csv,conf,v9 · PyCon US 2025 · csv,conf,v8 · NYC SOD 2022
- Full list: External Resources
These pages predate the wiki rewrite. Their content has been integrated into the new structure but the originals are kept for backwards-compatibility with external links:
- Cookbook (legacy) — original recipes; new Cookbook expands them
- qsv cheat sheet — pre-rewrite infographic & quick reference (WIP)
- Luau Development — folded into Scripting (Luau / Python)
- Luau Helper Functions Examples — referenced from Scripting (Luau / Python)
-
describegptmodel notes — folded into AI & Documentation -
xsv 0.13.0
statsvs qsv 1.0.0stats— referenced from Comparison vs others
This wiki is itself a git repo at https://github.com/dathere/qsv.wiki.git. See Contributing to the Wiki for clone/edit/push instructions and the verification checklist.