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BREAKING CHANGE: Arbitrary `impl RecordBatchReader` is no longer accepted, it must be made into `Box<dyn RecordBatchReader>`. This PR replaces `IntoArrow` with a new trait `Scannable` to define input row data. This provides the following advantages: 1. **We can implement `Scannable` for more types than `IntoArrow`, such as `RecordBatch` and `Vec<RecordBatch>`.** The `IntoArrow` trait was implemented for arbitrary `T: RecordBatchReader`, and the Rust compiler would prevent us from implementing it for foreign types like `RecordBatch` because (theoretically) those types might implement `RecordBatchReader` in the future. That's why we implement `Scannable` for `Box<dyn RecordBatchReader>` instead; since it's a concrete type it doesn't block implementing for other foreign types. 2. **We can potentially replay `Scannable` values**. Previously, we had to choose between buffering all data in memory and supporting retries of writes. But because `Scannable` things can optionally support re-scanning, we now have a way of supporting retries while also streaming. 3. **`Scannable` can provide hints like `num_rows`, which can be used to schedule parallel writers.** Without knowing the total number of rows, it's difficult to know whether it's worth writing multiple files in parallel. We don't yet fully take advantage of (2) and (3) yet, but will in future PRs. For (2), in order to be ready to leverage this, we need to hook the `Scannable` implementation up to Python and NodeJS bindings. Right now they always pass down a stream, but we want to make sure they support retries when possible. And for (3), this will need to be hooked up to #2939 and to a pipeline for running pre-processing steps (like embedding generation). ## Other changes * Moved `create_table` and `add_data` into their own modules. I've created a follow up issue to split up `table.rs` further, as it's by far the largest file: https://github.com/lancedb/lancedb/issues/2949 * Eliminated the `HAS_DATA` generic for `CreateTableBuilder`. I didn't see any public-facing places where we differentiated methods, which is why I felt this simplification was okay. * Added an `Error::External` variant and integrated some conversions to allow certain errors to pass through transparently. This will fully work once we upgrade Lance and get to take advantage of changes in https://github.com/lance-format/lance/pull/5606 * Added LZ4 compression support for write requests to remote endpoints. I checked and this has been supported on the server for > 1 year. --------- Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
LanceDB JavaScript SDK
A JavaScript library for LanceDB.
Installation
npm install @lancedb/lancedb
This will download the appropriate native library for your platform. We currently support:
- Linux (x86_64 and aarch64 on glibc and musl)
- MacOS (Intel and ARM/M1/M2)
- Windows (x86_64 and aarch64)
Usage
Basic Example
import * as lancedb from "@lancedb/lancedb";
const db = await lancedb.connect("data/sample-lancedb");
const table = await db.createTable("my_table", [
{ id: 1, vector: [0.1, 1.0], item: "foo", price: 10.0 },
{ id: 2, vector: [3.9, 0.5], item: "bar", price: 20.0 },
]);
const results = await table.vectorSearch([0.1, 0.3]).limit(20).toArray();
console.log(results);
The quickstart contains more complete examples.
Development
See CONTRIBUTING.md for information on how to contribute to LanceDB.