Daniel RammerandClaude Opus 5
4bb0effcb2
Three cleanups to the LsmWriteSpec surface, all removing something: `with_no_maintained_indexes` is gone. `with_maintained_indexes` now takes `impl Into<Option<Vec<String>>>`, so `None` asks for every supported index, a list pins an exact set, and an empty list maintains none — one method covering what two did, and the argument reads the same as the field it sets. `IndexConfig::is_memwal_maintainable` is gone. What a memtable can build is lance's to say, and lance already says it via `is_maintainable_index_type`; mirroring that onto a lancedb type only added a place for the two to drift. `resolve_maintained_indexes` is now public and takes `&[IndexConfig]` rather than a table. It was already the whole of the resolution rules — infer from the committed set, or validate a named one — and a server installing specs on a caller's behalf needs exactly those rules. Sharing it means sophon no longer keeps a second copy that could disagree about what an absent list means, and the error now names the table's indexes so a rejected call says what was actually available. 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.