Schema#

class polars.Schema(schema: Mapping[str, DataType] | Iterable[tuple[str, DataType]])[source]

Ordered mapping of column names to their data type.

Parameters:

schema: The schema definition given by column names and their associated instantiated Polars data type. Accepts a mapping or an iterable of tuples.

Examples

Define a schema by passing instantiated data types.

>>> schema = pl.Schema({"foo": pl.Int8(), "bar": pl.String()})
>>> schema
Schema({'foo': Int8, 'bar': String})

Access the data type associated with a specific column name.

>>> schema["foo"]
Int8

Access various schema properties using the names, dtypes, and len methods.

>>> schema.names()
['foo', 'bar']
>>> schema.dtypes()
[Int8, String]
>>> schema.len()
2

Methods:

`dtypes`	Get the data types of the schema.
`len`	Get the number of columns in the schema.
`names`	Get the column names of the schema.