Will Jones
5c1b44020a
`cargo deny` did not check crate-level dependency declarations against `[workspace.dependencies]`, so a crate used by both the core crate and the bindings could be declared independently in each one and drift. For example `tokio` was pinned at `1.23` in `rust/lancedb` and `1.40` in `python`, and `pin-project` at `1.0.7` in the workspace table but `1.1.5` in `python`. This PR turns on cargo-deny's `bans.workspace-dependencies` lint, which fails when a dependency is used by more than one member without going through `workspace = true`, and when a `[workspace.dependencies]` entry is used by nobody. Enabling it surfaced 12 violations. Fixing them means adding `bytes`, `lancedb`, `serde`, `serde_json`, `tempfile`, `tokio`, and `uuid` to `[workspace.dependencies]`, and pointing the `arrow`, `arrow-buffer`, `async-trait`, `chrono`, and `pin-project` declarations at the entries that already existed. `Cargo.lock` is unchanged, so resolution is the same as before. The shared `chrono` entry now carries `default-features = false, features = ["clock"]`, matching what `nodejs` and `python` already asked for — cargo ignores a member's `default-features = false` unless the workspace entry sets it too. On the targets we build, `clock` covers everything `rust/lancedb` was getting from chrono's defaults. Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
LanceDB Python SDK
A Python library for LanceDB.
Installation
pip install lancedb
Pre-Haswell x86_64 hosts: lancedb-compat
The default lancedb wheel targets x86-64-haswell (AVX2 + FMA + F16C) for full performance on modern hardware. Pre-Haswell hosts — Intel Sandy Bridge / Ivy Bridge / Westmere; AMD Bulldozer / Piledriver / Steamroller — don't have AVX2 and crash with Illegal instruction at import lancedb.
For those hosts, install the lancedb-compat package instead:
pip install lancedb-compat
Same Python API (import lancedb works as usual). The compat wheel is compiled at the x86-64-v2 baseline (Nehalem-class) and uses runtime SIMD dispatch in the embedded lance crate to pick the right kernel tier (scalar / AVX / AVX+FMA / AVX2+FMA / AVX-512) at load time, so it still goes fast on modern hardware while running cleanly on the pre-Haswell silicon. Use lance.simd_info() from Python to verify which tier was selected.
lancedb and lancedb-compat install to the same lancedb/ namespace and conflict at install time. Pick one. To switch, pip uninstall lancedb first, then pip install lancedb-compat (or vice-versa).
If you need a custom baseline (or lancedb-compat isn't yet published for your platform), build from source with the override:
RUSTFLAGS="-C target-cpu=x86-64-v2" maturin build --release
pip install ./target/wheels/lancedb-*.whl
Preview Releases
Stable releases are created about every 2 weeks. For the latest features and bug fixes, you can install the preview release. These releases receive the same level of testing as stable releases, but are not guaranteed to be available for more than 6 months after they are released. Once your application is stable, we recommend switching to stable releases.
pip install --pre --extra-index-url https://pypi.fury.io/lancedb/ lancedb
Usage
Basic Example
import lancedb
db = lancedb.connect('<PATH_TO_LANCEDB_DATASET>')
table = db.open_table('my_table')
results = table.search([0.1, 0.3]).limit(20).to_list()
print(results)
Development
See CONTRIBUTING.md for information on how to contribute to LanceDB.