Files
lancedb/docs
lancedb-gatefixer[bot] 7466dc9d1d fix(python): reject embedding source updates without vectors
Fixes #4761

`Table.update` does not compute embeddings, so changing an embedding source
column could leave the previous embedding in place. Source-column updates now
raise `ValueError` unless every associated vector column is supplied in the same
call.

The guard reads Python embedding metadata and native `lancedb::column_definitions`
without loading embedding models. It uses Lance's field-path parser for quoted
targets and covers synchronous and asynchronous local and remote tables. Supplying
every associated vector column, vector-only updates, and unrelated updates remain
supported.

This is a breaking change for source-only updates. The API documentation and
Update rows guide explain the requirement and the `merge_insert` alternative for
regenerating embeddings.

Validation at the reviewed head covered 44 targeted public update cases and the
full Python suite (3107 passed, 162 skipped, 70 deselected). All applicable
exact-head checks and workflows completed successfully.
2026-11-03 07:07:35 +08:00
..

LanceDB Documentation

For website guides in docs/web, start with Documentation in CONTRIBUTING.md. That covers editing pages, generated examples, previews, availability and drafts.

This page covers the SDK reference in docs/src, built with MkDocs. Its GitHub Actions workflow builds and deploys on pushes to main, so it can include unreleased APIs. That is separate from the release editions of the Mintlify website.

Building the docs

Setup

  1. Install LanceDB Python. See setup in Python contributing guide. Run make develop to install the Python package.
  2. Install documentation dependencies. From LanceDB repo root: pip install -r docs/requirements.txt

Preview the docs

Run these commands from the LanceDB repository root. The subshell changes into docs to load mkdocs.yml, while leaving your shell in the repository root.

(cd docs && PYTHONPATH=. mkdocs serve)

If you want to just generate the HTML files:

(cd docs && PYTHONPATH=. mkdocs build)

If successful, you should see a docs/site directory in the repository root that you can verify locally.

Adding examples

To make sure examples are correct, we put examples in test files so they can be run as part of our test suites.

You can see the tests are at:

  • Python: python/python/tests/docs
  • Typescript: nodejs/examples/

Checking python examples

cd python
pytest -vv python/tests/docs

Checking typescript examples

The examples depend on @lancedb/lancedb at file:../dist, so the package must be built before running the tests. This uses pnpm; see the Typescript contributing guide for the toolchain setup.

pushd nodejs
pnpm install
pnpm build
popd

Then you can run the examples by going to the nodejs/examples directory, which is a separate pnpm package with its own lockfile:

pushd nodejs/examples
pnpm install
pnpm test
popd

API documentation

Python

The Python API documentation is organized based on the file docs/src/python/python.md. We manually add entries there so we can control the organization of the reference page. However, this means any new types must be manually added to the file. No additional steps are needed to generate the API documentation.

Typescript

The typescript API documentation is generated from the typescript source code using typedoc.

When new APIs are added, you must manually re-run the typedoc command to update the API documentation. The new files should be checked into the repository.

pushd nodejs
# `pnpm docs` would invoke pnpm's built-in `docs` command, not the script.
pnpm run docs
popd