Backend#

class nominal.ibis.Backend(*args, **kwargs)#

Bases: SQLBackend, NoUrl

Ibis backend executing queries against the Nominal SQL API.

compiler = <nominal.ibis._backend.NominalCompiler object>#

name = 'nominal'#

supports_python_udfs = False#

supports_temporary_tables = False#

property version: str#

Return the version of the backend engine.

For database servers, return the server version.

For others such as SQLite and pandas return the version of the underlying library or application.

Returns#

str: The backend version

workspace_rid: str#

create_table(*args, **kwargs)#

Create a new table.

Parameters#

name: Name of the new table.
obj: An Ibis table expression or pandas table that will be used to extract the schema and the data of the new table. If not provided, schema must be given.
schema: The schema for the new table. Only one of schema or obj can be provided.
database: Name of the database where the table will be created, if not the default.
temp: Whether a table is temporary or not
overwrite: Whether to clobber existing data

Returns#

Table: The table that was created.

Return type:: Table

create_view(*args, **kwargs)#

Create a view from an Ibis expression.

Parameters#

name: The name of the view to create.
obj: The Ibis expression to create the view from.
database: The database that the view should be created in.
overwrite: If True, replace an existing view with the same name.

Returns#

ir.Table: A table expression representing the view.

Return type:: Table

disconnect()#

No-op: the gRPC channel belongs to the NominalClient.

do_connect(client)#

Use an existing client and fetch the SQL catalog.

Parameters:

client (NominalClient)

Authenticated Nominal client. Queries run in its default workspace, either the one pinned in the profile or the tenant default.

drop_table(*args, **kwargs)#

Drop a table from the backend.

Parameters#

name: The name of the table to drop
database: The database that the table is located in.
force: If True, do not raise an error if the table does not exist.

drop_view(*args, **kwargs)#

Drop a view from the backend.

Parameters#

name: The name of the view to drop.
database: The database that the view is located in.
force: If True, do not raise an error if the view does not exist.

execute(expr, /, *, params=None, limit=None, **kwargs)#

Execute an Ibis expression and return a pandas DataFrame, Series, or scalar.

Parameters#

expr: Ibis expression to execute.
params: Mapping of scalar parameter expressions to value.
limit: An integer to effect a specific row limit. A value of None means no limit. The default is in ibis/config.py.
kwargs: Keyword arguments

Returns#

DataFrame | Series | scalar: The result of the expression execution.

Return type:: Any

get_schema(table_name, *, catalog=None, database=None)#

Return type:: Schema

list_tables(*, like=None, database=None)#

Return the sorted names of the tables in the Nominal SQL catalog.

Parameters:

like (str | None)

Regular expression; return only names that contain a match.
database (tuple[str, str] | str | None)

Ignored. The catalog has a single database.

Return type:

list[str]

raw_sql(query)#

Return type:: Table

to_pyarrow(expr, /, *, params=None, limit=None, **kwargs)#

Execute the expression and return its result as a PyArrow Table, ChunkedArray, or Scalar.

Return type:: Any

to_pyarrow_batches(expr, /, *, params=None, limit=None, chunk_size=1_000_000, **kwargs)#

Execute the expression, streaming record batches without materializing the result.

Closing the reader releases the active query stream. Errors encountered while reading batches are reported as PyArrow exceptions.

Return type:: RecordBatchReader