`execute_query` / `execute_query_async` can now bind values to `$1` /
`$name` placeholders instead of splicing them into the SQL text. The
values travel as Arrow, so a float32 keeps its exact bits and type and a
vector stays a compact `FixedSizeList` (3 KB for 768 dims rather than ~9
KB of decimal literals parsed back as Float64).
```rust
db.execute_query_async("SELECT id FROM docs ORDER BY distance(vector, $vector) LIMIT $k")
.parameters(batch) // one-row RecordBatch
.execute()
.await?;
```
```python
db.execute_query(sql, parameters={"vector": np.float32_vector, "k": 10})
```
- A statement with parameters is sent on one `DoExchange`: the first
message carries the `CommandStatementQuery` descriptor and the parameter
schema, the second the one-row batch, and the result rows stream back on
the same call. Statements without parameters keep `PollFlightInfo` +
`DoGet` unchanged.
- Column `i` binds `$<i+1>`; a column whose name is not a number also
binds `$<name>`. Python accepts a list (positional), a dict (named), or
a one-row `RecordBatch` / `Table`; 1-D numpy / pyarrow arrays become a
`FixedSizeList` of their element type.
- A parameterized query runs on its call: `cancel()`, dropping the
handle before reading, or dropping the reader ends the call and stops
the server-side statement. It is still registered for `describe_query`.
- `Database::execute_query_async` now takes an `ExecuteQueryRequest`
options struct.
Server side: lancedb/sophon#8256.
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