An open source multi-tool for exploring and publishing data https://datasette.io
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Alex Garcia b40b06f1cb Emit a db.query span around Database.execute()
Datasette's existing tracer times a "sql" block that wraps a good deal
more than the query itself - queueing onto the thread pool, the pool
wait, and result marshalling all disappear into one number. That is
simonw/datasette#1730, "SQL tracing should much more closely track the
SQL query execution", open since 2022. A db.query span here is the outer
half of the answer; a later change adds the inner span drawn around the
sqlite3 call itself, and the gap between the two is exactly the thread
pool wait the current tracer folds away.

The span carries OTel semantic-convention attributes (db.system,
db.namespace, db.query.text) plus a few datasette.* ones. db.query.text
goes through sql_attribute(), which caps it at 2048 characters, because
on a public instance the SQL is attacker-supplied and unbounded. Only
len(params) is recorded, never a parameter value.

The existing `with trace(...)` wrapper stays exactly where it is and the
new span nests inside it. This change removes nothing: ?_trace=1 and the
trace_debug setting keep working unchanged. The two systems are
independent code paths.

Exception handling on the span is explicit rather than inherited from
start_as_current_span's defaults, which would record the exception and
set StatusCode.ERROR on anything passing through. That is wrong here
because some SQL failures are the expected answer. ArrayFacet.suggest()
runs json_type(<column>) against every column precisely to discover
which ones raise "malformed JSON", and passes log_sql_errors=False to
say so. Left to the defaults, a table with N text columns marks N
queries per page as failed - burying genuine failures and tripping any
alerting keyed on span status. Measured on a plain table page before
this: 4 error spans out of 225, all expected. Suppressed errors now
leave the status UNSET and set datasette.sql_error_suppressed instead,
so they stay discoverable without reading as failures.

QueryInterrupted still sets ERROR unconditionally. That is not quite
right either - facet suggestion is designed to time out - but the fix
needs its own reasoning and lands separately.

Behaviour change worth calling out: time_limit_ms is hoisted out of
sql_operation_in_thread so the span can record it on the event loop. It
is therefore read at call time rather than at thread-execution time.
Benign in practice, since ds.sql_time_limit_ms is set at startup, but it
is a real change.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-01 16:24:15 -07:00
.github check-latest: true, add 3.15 to test matrix, to test RCs (#2895) 2026-09-01 13:37:15 -07:00
datasette Emit a db.query span around Database.execute() 2026-09-01 16:24:15 -07:00
demos Fixed an unnecessary f-string 2024-02-04 10:15:21 -08:00
docs Release 1.0a38 2026-08-06 11:20:25 -07:00
tests Emit a db.query span around Database.execute() 2026-09-01 16:24:15 -07:00
.coveragerc Configure code coverage, refs #841, #843 2020-06-13 13:48:23 -07:00
.dockerignore Build Dockerfile with SpatiaLite 5, refs #1249 2021-03-26 21:27:40 -07:00
.git-blame-ignore-revs Ignore Black commits in git blame, refs #1716 2022-04-22 14:58:46 -07:00
.gitattributes New explicit versioning mechanism 2020-10-28 20:38:15 -07:00
.gitignore Ignore ignored/ directory 2026-06-25 21:20:29 -07:00
.isort.cfg Used isort to re-order my imports 2018-05-14 00:04:23 -03:00
.prettierrc .prettierrc, refs #1166 2020-12-31 13:25:44 -08:00
.readthedocs.yaml dependency-groups and uv (#2611) 2025-12-11 17:32:58 -08:00
CODE_OF_CONDUCT.md Add code of conduct again 2022-03-15 08:38:42 -07:00
codecov.yml codecov should not be blocking 2020-07-02 21:29:32 -07:00
Dockerfile Upgrade Docker images to Python 3.11, closes #1853 2022-10-25 12:04:53 -07:00
Justfile Add Prettier check to lint recipe (#2821) 2026-07-03 09:50:35 -07:00
LICENSE Initial commit 2017-10-22 17:39:03 -07:00
MANIFEST.in Include LICENSE in sdist (#1043) 2020-10-23 13:54:34 -07:00
package-lock.json Bump rollup from 3.29.5 to 3.30.0 (#2651) 2026-03-30 10:54:48 -07:00
package.json Bump rollup from 3.29.5 to 3.30.0 (#2651) 2026-03-30 10:54:48 -07:00
pyproject.toml Add opentelemetry-api dependency and datasette/telemetry.py scaffolding 2026-09-01 16:24:15 -07:00
pytest.ini Initial Playwright setup plus first test 2026-06-14 16:39:55 -07:00
README.md Replace Glitch with Codespaces, closes #2488 2025-05-28 19:17:22 -07:00
ruff.toml Upgrade to ruff>=0.16.0 (#2857) 2026-07-25 15:47:08 -07:00
setup.cfg Switch to ruff and fix all lint errors, refs #2630 2026-01-23 20:43:16 -08:00
test-in-pyodide-with-shot-scraper.sh Test against pyodide/v314.0.0 2026-06-22 10:11:56 -07:00

Datasette

PyPI Changelog Python 3.x Tests Documentation Status License docker: datasette discord

An open source multi-tool for exploring and publishing data

Datasette is a tool for exploring and publishing data. It helps people take data of any shape or size and publish that as an interactive, explorable website and accompanying API.

Datasette is aimed at data journalists, museum curators, archivists, local governments, scientists, researchers and anyone else who has data that they wish to share with the world.

Explore a demo, watch a video about the project or try it out on GitHub Codespaces.

Want to stay up-to-date with the project? Subscribe to the Datasette newsletter for tips, tricks and news on what's new in the Datasette ecosystem.

Installation

If you are on a Mac, Homebrew is the easiest way to install Datasette:

brew install datasette

You can also install it using pip or pipx:

pip install datasette

Datasette requires Python 3.8 or higher. We also have detailed installation instructions covering other options such as Docker.

Basic usage

datasette serve path/to/database.db

This will start a web server on port 8001 - visit http://localhost:8001/ to access the web interface.

serve is the default subcommand, you can omit it if you like.

Use Chrome on OS X? You can run datasette against your browser history like so:

 datasette ~/Library/Application\ Support/Google/Chrome/Default/History --nolock

Now visiting http://localhost:8001/History/downloads will show you a web interface to browse your downloads data:

Downloads table rendered by datasette

metadata.json

If you want to include licensing and source information in the generated datasette website you can do so using a JSON file that looks something like this:

{
    "title": "Five Thirty Eight",
    "license": "CC Attribution 4.0 License",
    "license_url": "http://creativecommons.org/licenses/by/4.0/",
    "source": "fivethirtyeight/data on GitHub",
    "source_url": "https://github.com/fivethirtyeight/data"
}

Save this in metadata.json and run Datasette like so:

datasette serve fivethirtyeight.db -m metadata.json

The license and source information will be displayed on the index page and in the footer. They will also be included in the JSON produced by the API.

datasette publish

If you have Heroku or Google Cloud Run configured, Datasette can deploy one or more SQLite databases to the internet with a single command:

datasette publish heroku database.db

Or:

datasette publish cloudrun database.db

This will create a docker image containing both the datasette application and the specified SQLite database files. It will then deploy that image to Heroku or Cloud Run and give you a URL to access the resulting website and API.

See Publishing data in the documentation for more details.

Datasette Lite

Datasette Lite is Datasette packaged using WebAssembly so that it runs entirely in your browser, no Python web application server required. Read more about that in the Datasette Lite documentation.