Files
lancedb/python
Jonathan HsiehandClaude Opus 5 60a1b4c219 feat(secrets): named Secrets, bindings, and namespace addressing (#4150)
Adds the client half of database-scoped named Secrets: a Secret is a
name and
an opaque value stored by the service, and a Function binds one to the
environment variable its library already reads. Secrets are addressed by
a
namespace path plus a name.

The UDF body is unchanged and stays portable — it reads `OPENAI_API_KEY`
the
way it always did, and the binding is what puts a value there:

```python
db.create_secret("openai-prod", os.environ["OPENAI_API_KEY"])
function = db.create_function(
    analyze_caption,
    secrets=[
        EnvVarSecret(secret_name="openai-prod", env_variable="OPENAI_API_KEY")
    ],
)
function.secret_bindings   # the Secret's name, never its value
```

- `create_secret` / `alter_secret` / `list_secrets` / `describe_secret`
/
`drop_secret` on sync, async and remote connections, with the pyo3
binding
and the Rust client behind them. Each takes `namespace_path`
keyword-only,
  defaulting to the root.
- **There is no read API, by construction rather than by policy** — no
code
  path returns a stored credential, and `describe_secret` answers with
  metadata only.
- `EnvVarSecret` is a pure local constructor: it contacts no server, so
it
cannot fail on a Secret that does not exist. It exists so that a bare
string
in that position — which would be a credential — is a `TypeError` rather
  than a plausible-looking mistake that reads identically in a diff.
- `create_function(..., secrets=[...])` carries the bindings as
`secret_bindings`: a list of `SecretBinding` tagged by `kind`, so a
later
delivery mode is a variant rather than a sibling field. The value never
travels — it is resolved by the service when the Function runs, which is
what
lets a rotation reach columns already pinned to an older
FunctionVersion.
- A binding names its Secret as a `SecretReference` of `{name,
namespace_path}`
rather than one joined string, so no delimiter has to be excluded from
every
name and segment forever, and `ClientConfig.id_delimiter` cannot
contradict
  an identity built on a fixed separator.
- A root namespace is omitted from the request body rather than sent
empty, so
  a root request is byte-identical to one from a client that predates
  namespaces. Tests pin it.

This is the client surface the design's §4 describes; the service side
lives in
sophon.

**Previously split across two PRs.** Namespace addressing was #4151,
stacked on
this one; it is folded in here so the Secret identity contract — name,
namespace path, and the binding that carries both — is reviewable as one
piece
rather than as a shape introduced and then replaced.

## Identifier safety, merged from #4189

**#4189 is merged into this branch**, so the client half of Secrets and
the
guards on the identity it puts in the URL are one PR. What it added:

- Components are checked where the identifier is built, before a request
is
  constructed. `create_secret("../jobs", value)` no longer resolves to
`/v1/jobs/create` and delivers a credential-bearing body to a route with
none
  of this one's body suppression.
- Each component is percent-encoded and joined by the delimiter, so
nothing
  inside a component can end the path segment or add one.
- A component may not be empty, a relative segment (`.`, `..`, and their
`%2e`
spellings), or the delimiter itself — the three ways a component erases
a
boundary the split has to recover. `["prod", ""]` joined to `prod$`,
which
  reads back as `["prod"]`.
- `$` is the only accepted `id_delimiter`, refused at client
construction.
`ClientConfig.id_delimiter` remains, since the identifier grammar comes
from
the Lance REST catalog standard, but a value that would produce
identifiers no
  service splits the caller's way is now an error where it was written.
- One `build_object_identifier` and one character set serve tables,
namespaces,
  Secrets, Functions and materialized views.

Components are checked for *addressability*, not a character set: the
name's
own grammar stays each object's own, so a catalog database keeps the `/`
that
`RemoteCatalog::validate_name` allows.

## Known shortcoming

`secret_bindings` is omitted from a registration body when empty, so a
client
that binds nothing sends what a client without bindings sends. When a
client
does bind a Secret and the service does not know the field, the field is
ignored: registration succeeds, the returned version carries no
bindings, and
the Function fails at execution with the variable unset, far from the
call that
asked for it.

`ServerVersion` is how this codebase refuses a feature the service is
too old
for, and it gates five features already. It does not gate this one: it
is held
per table, and registering a Function is a database-level call. Noted at
the
field in `remote/db.rs`; wiring the gate is follow-up work.

**Tests:** lancedb lib 1340 passed, `first_class_function_slice1` 9,
`first_class_function_slice2` 3, plus Python tests across both slices.
Rebased onto `main` after #4176 (OCI Function identity), #4191 (`.`/`..`
table
names) and #4195 (remote catalogs).

🤖 Generated with [Claude Code](https://claude.com/claude-code)

https://claude.ai/code/session_01UfmeJ533rQDnPBkMtjerV6

---------

Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-16 17:00:23 -07:00
..
2025-01-29 08:27:07 -08:00
2024-04-05 16:22:59 -07:00

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

Threading in CPU-limited containers

LanceDB uses separate pools for compute work and storage I/O. On a container with two visible CPUs, current releases intentionally use one compute worker by default; no manual configuration is needed. If every query logs an I/O core reservation warning on a two-CPU container, upgrade from LanceDB 0.21.1 or earlier.

The two commonly tuned environment variables control different resources:

  • LANCE_CPU_THREADS overrides the number of compute workers. One worker is the appropriate setting for a two-CPU container when an explicit override is needed.
  • LANCE_IO_THREADS controls concurrent storage operations, not reserved CPU cores. Its default can be greater than the number of CPUs because I/O workers spend much of their time waiting for storage.

Keep the defaults unless measurements show that the workload benefits from an override. See the Lance threading model for the current defaults and tuning guidance.

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.