patito.Database.to_relation

Database.to_relation(derived_from)

Create a new relation object based on data source.

The given data will be represented as a relation associated with the database. Database(x).to_relation(y) is equivalent to Relation(y, database=Database(x)).

Parameters

derived_from (RelationSource) – One of either a polars or pandas DataFrame, a pathlib.Path to a parquet or CSV file, a SQL query string, or an existing relation.

Example

>>> import patito as pt
>>> db = pt.Database()
>>> db.to_relation("select 1 as a, 2 as b").to_df()
shape: (1, 2)
┌─────┬─────┐
│ a   ┆ b   │
│ --- ┆ --- │
│ i64 ┆ i64 │
╞═════╪═════╡
│ 1   ┆ 2   │
└─────┴─────┘
>>> db.to_relation(pt.DataFrame({"c": [3, 4], "d": ["5", "6"]})).to_df()
shape: (2, 2)
┌─────┬─────┐
│ c   ┆ d   │
│ --- ┆ --- │
│ i64 ┆ str │
╞═════╪═════╡
│ 3   ┆ 5   │
├╌╌╌╌╌┼╌╌╌╌╌┤
│ 4   ┆ 6   │
└─────┴─────┘

Return type

Relation