Files
lancedb/docs/src/python/pydantic.md
Lei Xu b315ea3978 [Python] Pydantic vector field with default value (#474)
Rename `lance.pydantic.vector` to `Vector` and deprecate `vector(dim)`
2023-09-08 22:35:31 -07:00

37 lines
1.3 KiB
Markdown

# Pydantic
[Pydantic](https://docs.pydantic.dev/latest/) is a data validation library in Python.
LanceDB integrates with Pydantic for schema inference, data ingestion, and query result casting.
## Schema
LanceDB supports to create Apache Arrow Schema from a
[Pydantic BaseModel](https://docs.pydantic.dev/latest/api/main/#pydantic.main.BaseModel)
via [pydantic_to_schema()](python.md##lancedb.pydantic.pydantic_to_schema) method.
::: lancedb.pydantic.pydantic_to_schema
## Vector Field
LanceDB provides a [`Vector(dim)`](python.md#lancedb.pydantic.Vector) method to define a
vector Field in a Pydantic Model.
::: lancedb.pydantic.Vector
## Type Conversion
LanceDB automatically convert Pydantic fields to
[Apache Arrow DataType](https://arrow.apache.org/docs/python/generated/pyarrow.DataType.html#pyarrow.DataType).
Current supported type conversions:
| Pydantic Field Type | PyArrow Data Type |
| ------------------- | ----------------- |
| `int` | `pyarrow.int64` |
| `float` | `pyarrow.float64` |
| `bool` | `pyarrow.bool` |
| `str` | `pyarrow.utf8()` |
| `list` | `pyarrow.List` |
| `BaseModel` | `pyarrow.Struct` |
| `Vector(n)` | `pyarrow.FixedSizeList(float32, n)` |