Will Jones
d2ca0ce0ab
Merge insert has always taken a list of columns to match on, and local tables have always joined on all of them. Remote tables did not: any list longer than one was rejected with `MergeInsertBuilder only supports a single 'on' column`, so a composite-key upsert was impossible against LanceDB Cloud and Enterprise from Rust, Python or TypeScript. The remote request now carries `on` as a list and sends it as one repeated query parameter per column — `?on=shard_key&on=id`. That is how the lance-namespace spec encodes an array-valued `on`, so the server receives a composite key in the shape it expects. A single column still serializes to `?on=id`, exactly what clients sent before, so existing callers are unaffected. A column repeated within `on` is now rejected client-side rather than sent for the server to reject with a 400. No binding changes were needed: `Table.merge_insert` in Python and `Table.mergeInsert` in TypeScript already accepted a list, it just could not reach a remote table. Both gain a test for composite keys, and the doc comments now say what passing several columns means. Part of [ENT-2084](https://linear.app/lancedb/issue/ENT-2084/mergeinsertintotablerequest-support-multiple-columns-for-the). ## Example ```python table.merge_insert(["shard_key", "id"]) \ .when_matched_update_all() \ .when_not_matched_insert_all() \ .execute(new_data) ``` A row whose `id` matches an existing row but whose `shard_key` differs is an insert, not an update. ## Not included Java. Java callers reach merge insert through `org.lance.namespace.LanceNamespace`, whose `MergeInsertIntoTableRequest.on` is a single string until lance-namespace 0.12 ([lance-namespace#363](https://github.com/lance-format/lance-namespace/pull/363), [lance#8915](https://github.com/lance-format/lance/pull/8915)). There is nothing in this repo's Java SDK to change until the `lance-core` pin can move. Sending more than one column requires a server that accepts the repeated parameter ([sophon#7571](https://github.com/lancedb/sophon/pull/7571)); an older server returns a 400 rather than silently merging on one column. Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
LanceDB Documentation
LanceDB docs are available at docs.lancedb.com.
The SDK docs are built and deployed automatically by Github Actions
whenever a commit is pushed to the main branch. So it is possible for the docs to show
unreleased features.
Building the docs
Setup
- Install LanceDB Python. See setup in Python contributing guide.
Run
make developto install the Python package. - Install documentation dependencies. From LanceDB repo root:
pip install -r docs/requirements.txt
Preview the docs
cd docs
mkdocs serve
If you want to just generate the HTML files:
PYTHONPATH=. mkdocs build -f docs/mkdocs.yml
If successful, you should see a docs/site directory 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