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docs/python-api-reference-gaps
2
Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
  Shengan ZhangandCursor
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64aeee84a8 |
feat(python): support bytes in lit() expressions (#3387)
Closes #3261. ## Summary Adds `bytes` to the accepted types of `lancedb.expr.lit()` so that binary scalars can be used in filter / projection expressions. The previous attempt in #3235 had to be reverted because DataFusion's SQL unparser does not support `Binary` / `LargeBinary` scalars, so any expression containing such a literal would fail in both `to_sql()` and `__repr__`. ## How `expr_to_sql_string` now has two paths: - **Fast path** (no binary literals): delegate to DataFusion's unparser unchanged. - **Slow path**: rewrite each `Binary(Some(bytes))` literal in the tree to a unique string-literal placeholder, run the unparser, then substitute `'<placeholder>'` with `X'<HEX>'` in the resulting SQL. `Binary(None)` / `LargeBinary(None)` are rewritten to `ScalarValue::Null` so the unparser emits plain `NULL`. This keeps DataFusion as the single source of truth for operator and function serialization, so binary literals work in every expression node type the unparser already supports — including nested cases like `contains(col("data"), lit(b"\xff"))`, `NOT (col == lit(b"..."))`, and `col.cast(...) == lit(b"...")`. ## Changes - `rust/lancedb/src/expr/sql.rs`: placeholder-substitution implementation. - `rust/lancedb/src/expr.rs`: 4 new unit tests covering binary literals in equality, compound predicates, scalar function calls, negation, and `NULL` binary literals. - `python/src/expr.rs`: `expr_lit` accepts `PyBytes` and produces `ScalarValue::Binary`. - `python/Cargo.toml` + `Cargo.lock`: pull in `datafusion-common` for `ScalarValue`. - `python/python/lancedb/expr.py`: extend `ExprLike` and `lit()` type annotations / docstrings with `bytes`. - `python/python/lancedb/_lancedb.pyi`: update `expr_lit` stub. - `python/tests/test_expr.py`: unit tests for `to_sql` / `repr` of binary literals and an integration test against a real `pa.binary()` column for equality / inequality / compound filters. ## Example ```python from lancedb.expr import col, lit, func # Equality against a binary column col("payload") == lit(b"\xca\xfe") # Expr((payload = X'CAFE')) # Nested inside a function call (previously failed) func("contains", col("data"), lit(b"\xff")) # Expr(contains(data, X'FF')) # repr() no longer crashes repr(lit(b"\xde\xad\xbe\xef")) # "Expr(X'DEADBEEF')" ``` ## Verification - [x] `cargo test -p lancedb --lib expr::` — 12/12 pass (was 9; +3 new tests) - [x] `cargo check --features remote --tests --examples` — clean - [x] `cargo clippy --features remote --tests --examples` — no warnings - [x] `cargo fmt --all -- --check` — clean - [x] `pytest python/tests/test_expr.py` — 76/76 pass (was 74; +2 new tests) - [x] `ruff check python` / `ruff format --check python` — clean ## Follow-ups (not in this PR) Issue #3261 also raises the possibility of a *truncated* `__repr__` for very large binary literals. This PR keeps `__repr__` exact (it forwards to `to_sql()`), since truncating display output would diverge from the SQL that actually gets executed. A display-only truncation could be added in a follow-up by giving `__repr__` its own renderer. Made with [Cursor](https://cursor.com) Co-authored-by: Cursor <cursoragent@cursor.com> |
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|
Shengan Zhang
|
650f173236 |
feat(python): add IVF_HNSW_FLAT vector index support (#3366)
## Summary Wire up `IVF_HNSW_FLAT` in the Rust core and Python SDK. The index was documented at https://docs.lancedb.com/indexing/vector-index but `lancedb.Table.create_index(index_type="IVF_HNSW_FLAT")` raised `ValueError: Unknown index type IVF_HNSW_FLAT` — the underlying `pylance` already accepted it, only the LanceDB wrapper was missing the wiring. **Rust core (`rust/lancedb`):** - Add `Index::IvfHnswFlat` / `IndexType::IvfHnswFlat` variants and the `IvfHnswFlatIndexBuilder` (modelled on `IvfHnswSqIndexBuilder`). - Build Lance params via the existing `VectorIndexParams::ivf_hnsw(...)` helper, keeping symmetry with the other `IVF_HNSW_*` variants. - Forward the variant in `RemoteTable::create_index` and add two parametrised tests (default + customised config) for the JSON serialisation. - New `NativeTable` integration test (`test_create_index_ivf_hnsw_flat`). **Python binding (`python/`):** - New `HnswFlat` dataclass + backwards-compat `IvfHnswFlat` alias. - PyO3 `extract_index_params` recognises the `HnswFlat` config. - `LanceTable.create_index(index_type="IVF_HNSW_FLAT", …)` and the sync `RemoteTable.create_index` both dispatch to the new config. - `IndexStatistics.index_type` `Literal` and `_lancedb.pyi` stubs cover the new type so `pyright`/`make check` stays clean. - Async integration tests (`HnswFlat` + `IvfHnswFlat` alias) and a sync dispatcher test, mirroring the existing `IVF_HNSW_SQ` coverage. - Existing `test_index_statistics_index_type_lists_all_supported_values` updated to include `IVF_HNSW_FLAT`. A matching Node.js / TypeScript binding is in a follow-up PR. Closes #3331 ## Test plan - [ ] \`cargo check --quiet --features remote --tests --examples\` - [ ] \`cargo test --quiet --features remote -p lancedb\` (covers the new \`test_create_index_ivf_hnsw_flat\` and the two new parametrised \`RemoteTable::create_index\` cases) - [ ] \`cargo fmt --all\` / \`cargo clippy --quiet --features remote --tests --examples\` - [ ] \`cd python && make develop && make check && make test\` (covers the two new async tests, the alias test, the dispatcher test, and the updated \`test_index_statistics_index_type_lists_all_supported_values\` assertion) |