# uwdata/arquero

Query processing and transformation of array-backed data tables.

Repository: https://github.com/uwdata/arquero
Canonical: https://ross.abutalabs.com/products/arquero
Homepage: https://idl.uw.edu/arquero/
Language: JavaScript
License: BSD-3-Clause
License Family: permissive
Topics: data, query, database, table, dataframe, transform, arrays
Last push: 2025-05-29T22:26:36+00:00

## Health v2 (maintenance only)
Score: 45/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 24, release rhythm 40, longevity 100
- inputs: {"age_days": 2192, "days_push": 461, "days_rel": 461, "gap_med": 13, "n_releases_24m": 8}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1534, forks 74 (observed 2026-08-28T04:04:59.728810+00:00)

## What it is
Arquero is a JavaScript library for query processing and transformation of array-backed, column-oriented data tables. It offers a fluent, dplyr-inspired API supporting filter, aggregation, window, join, and reshaping operations over arrays, typed arrays, and Apache Arrow columns.

## Use cases
- filter and transform large in-memory tables in JavaScript
- perform group-by aggregations and window functions on data frames
- join and reshape datasets in the browser or Node.js
- query Apache Arrow columnar data with a fluent API
- clean and wrangle CSV or JSON data for analysis
- run dplyr-style data pipelines without a database server

## When to choose
- you need fast in-memory data frame operations in JavaScript or TypeScript
- you want dplyr-like table verbs in the browser or Node.js
- you work with Apache Arrow columns or typed arrays
- you need million+ row transformations without a backend database

## When to avoid
- you need persistent storage or SQL queries over disk-based data
- you work primarily in Python or R with pandas or dplyr
- you need distributed or out-of-core processing of very large datasets
- you only need simple array utilities without table semantics

## Facets
- artifact type: library
- maturity: stable
- function: database, etl, data-science, serialization
- domain: data-science, developer-tools, analytics
- platform: browser, cross-platform
- tags: dataframe, query-processing, relational-algebra, dplyr-inspired, apache-arrow, column-oriented, data-wrangling, table-transformations, data-engineering, nodejs, javascript

## Member repositories
- uwdata/arquero (main) score 45

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:04:59.728810+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T04:31:13.463222+00:00, confidence not recorded.
  - readme: https://github.com/uwdata/arquero (fetched 2026-08-28T04:04:59.728810+00:00, sha b536a5c22bc5)
  - homepage: https://idl.uw.edu/arquero/ (fetched 2026-08-29T11:33:23.405516+00:00, sha 1e0f1b0a3c44)
  - registry_npm: https://registry.npmjs.org/arquero (fetched 2026-08-29T11:33:23.414698+00:00, sha ae9e0a6f5ef4)
- Data as of 2026-08-30T08:39:29.467469+00:00.