Snowflake

Install Ibis in Python and connect to Snowflake for working with in a pandas-like dataframe library

https://www.snowflake.com

Install

Install Ibis and dependencies for the Snowflake backend:

Install with the snowflake extra:

pip install 'ibis-framework[snowflake]'

And connect:

import ibis

con = ibis.snowflake.connect()
1
Adjust connection parameters as needed.

Install for Snowflake:

conda install -c conda-forge ibis-snowflake

And connect:

import ibis

con = ibis.snowflake.connect()
1
Adjust connection parameters as needed.

Install for Snowflake:

mamba install -c conda-forge ibis-snowflake

And connect:

import ibis

con = ibis.snowflake.connect()
1
Adjust connection parameters as needed.

Connect

ibis.snowflake.connect

con = ibis.snowflake.connect(
    user="user",
    password="password",
    account="safpqpq-sq55555",
    database="IBIS_TESTING/IBIS_TESTING",
)
Note

ibis.snowflake.connect is a thin wrapper around ibis.backends.snowflake.Backend.do_connect.

Connection Parameters

do_connect

do_connect(self, user, account, database, password=None, authenticator=None, connect_args=None, create_object_udfs=True, **kwargs)

Connect to Snowflake.

Parameters
Name Type Description Default
user str Username required
account str A Snowflake organization ID and a Snowflake user ID, separated by a hyphen. Note that a Snowflake user ID is a separate identifier from a username. See https://ibis-project.org/backends/Snowflake/ for details required
database str A Snowflake database and a Snowflake schema, separated by a /. See https://ibis-project.org/backends/Snowflake/ for details required
password str | None Password. If empty or None then authenticator must be passed. None
authenticator str | None String indicating authentication method. See https://docs.snowflake.com/en/developer-guide/python-connector/python-connector-example#connecting-with-oauth for details. Note that the authentication flow will not take place until a database connection is made. This means that ibis.snowflake.connect(...) can succeed, while subsequent API calls fail if the authentication fails for any reason. None
create_object_udfs bool Enable object UDF extensions defined by ibis on the first connection to the database. True
connect_args collections.abc.Mapping[str, typing.Any] | None Additional arguments passed to the SQLAlchemy engine creation call. None
kwargs typing.Any Additional arguments passed to the SQLAlchemy URL constructor. See https://docs.snowflake.com/en/developer-guide/python-connector/sqlalchemy#additional-connection-parameters for more details {}

ibis.connect URL format

In addition to ibis.snowflake.connect, you can also connect to Snowflake by passing a properly-formatted Snowflake connection URL to ibis.connect:

con = ibis.connect(f"snowflake://{user}:{password}@{account}/{database}")

Authenticating with SSO

Ibis supports connecting to SSO-enabled Snowflake warehouses using the authenticator parameter.

You can use it in the explicit-parameters-style or in the URL-style connection APIs. All values of authenticator are supported.

Explicit

con = ibis.snowflake.connect(
    user="user",
    account="safpqpq-sq55555",
    database="my_database/my_schema",
    warehouse="my_warehouse",
    authenticator="externalbrowser",
)

URL

con = ibis.connect(
    f"snowflake://{user}@{account}/{database}?warehouse={warehouse}",
    authenticator="externalbrowser",
)

Looking up your Snowflake organization ID and user ID

A Snowflake account identifier consists of an organization ID and a user ID, separated by a hyphen.

Note

This user ID is not the same as the username you log in with.

To find your organization ID and user ID, log in to the Snowflake web app, then click on the text just to the right of the Snowflake logo (in the lower-left-hand corner of the screen).

The bold text at the top of the little pop-up window is your organization ID. The bold blue text with a checkmark next to it is your user ID.

Snowflake Organization and User ID

Choosing a value for database

Snowflake refers to a collection of tables as a schema, and a collection of schema as a database.

You must choose a database and a schema to connect to. You can refer to the available databases and schema in the “Data” sidebar item in the Snowflake web app.

Snowflake Database

snowflake.Backend

add_operation

add_operation(self, operation)

Add a translation function to the backend for a specific operation.

Operations are defined in ibis.expr.operations, and a translation function receives the translator object and an expression as parameters, and returns a value depending on the backend.

begin

begin(self)

compile

compile(self, expr, limit=None, params=None, timecontext=None)

Compile an Ibis expression.

Parameters

Name Type Description Default
expr ibis.ibis.Expr Ibis expression required
limit str | None For expressions yielding result sets; retrieve at most this number of values/rows. Overrides any limit already set on the expression. None
params collections.abc.Mapping[ibis.ibis.Expr, typing.Any] | None Named unbound parameters None
timecontext tuple[pandas.pandas.Timestamp, pandas.pandas.Timestamp] | None Additional information about data source time boundaries None

Returns

Type Description
typing.Any The output of compilation. The type of this value depends on the backend.

connect

connect(self, *args, **kwargs)

Connect to the database.

Parameters

Name Type Description Default
*args Mandatory connection parameters, see the docstring of do_connect for details. ()
**kwargs Extra connection parameters, see the docstring of do_connect for details. {}

Notes

This creates a new backend instance with saved args and kwargs, then calls reconnect and finally returns the newly created and connected backend instance.

Returns

Type Description
ibis.backends.base.BaseBackend An instance of the backend

create_database

create_database(self, name, force=False)

Create a new database.

Parameters

Name Type Description Default
name str Name of the new database. required
force bool If False, an exception is raised if the database already exists. False

create_schema

create_schema(self, name, database=None, force=False)

Create a schema named name in database.

Parameters

Name Type Description Default
name str Name of the schema to create. required
database str | None Name of the database in which to create the schema. If None, the current database is used. None
force bool If False, an exception is raised if the schema exists. False

create_table

create_table(self, name, obj=None, *, schema=None, database=None, temp=False, overwrite=False, comment=None)

Create a table in Snowflake.

Parameters

Name Type Description Default
name str Name of the table to create required
obj pandas.pandas.DataFrame | pyarrow.pyarrow.Table | ibis.ibis.Table | None The data with which to populate the table; optional, but at least one of obj or schema must be specified None
schema ibis.ibis.Schema | None The schema of the table to create; optional, but at least one of obj or schema must be specified None
database str | None The name of the database in which to create the table; if not passed, the current database is used. None
temp bool Create a temporary table False
overwrite bool If True, replace the table if it already exists, otherwise fail if the table exists False
comment str | None Add a comment to the table None

create_view

create_view(self, name, obj, *, database=None, overwrite=False)

database

database(self, name=None)

Return a Database object for the name database.

Parameters

Name Type Description Default
name str | None Name of the database to return the object for. None

Returns

Type Description
ibis.backends.base.Database A database object for the specified database.

drop_database

drop_database(self, name, force=False)

Drop a database with name name.

Parameters

Name Type Description Default
name str Database to drop. required
force bool If False, an exception is raised if the database does not exist. False

drop_schema

drop_schema(self, name, database=None, force=False)

Drop the schema with name in database.

Parameters

Name Type Description Default
name str Name of the schema to drop. required
database str | None Name of the database to drop the schema from. If None, the current database is used. None
force bool If False, an exception is raised if the schema does not exist. False

drop_table

drop_table(self, name, database=None, schema=None, force=False)

Drop a table from Snowflake.

drop_view

drop_view(self, name, *, database=None, force=False)

execute

execute(self, expr, params=None, limit='default', **kwargs)

Compile and execute an Ibis expression.

Compile and execute Ibis expression using this backend client interface, returning results in-memory in the appropriate object type

Parameters

Name Type Description Default
expr ibis.ibis.Expr Ibis expression required
limit str For expressions yielding result sets; retrieve at most this number of values/rows. Overrides any limit already set on the expression. 'default'
params collections.abc.Mapping[ibis.ibis.Scalar, typing.Any] | None Named unbound parameters None
kwargs typing.Any Backend specific arguments. For example, the clickhouse backend uses this to receive external_tables as a dictionary of pandas DataFrames. {}

Returns

Type Description
DataFrame | Series | Scalar * Table: pandas.DataFrame * Column: pandas.Series * Scalar: Python scalar value

fetch_from_cursor

fetch_from_cursor(self, cursor, schema)

has_operation

has_operation(cls, operation)

insert

insert(self, table_name, obj, schema=None, database=None, overwrite=False)

Insert data into a table.

Parameters

Name Type Description Default
table_name str The name of the table to which data needs will be inserted required
obj pandas.pandas.DataFrame | ibis.ibis.Table | list | dict The source data or expression to insert required
schema str | None The name of the schema that the table is located in None
database str | None Name of the attached database that the table is located in. None
overwrite bool If True then replace existing contents of table False

list_databases

list_databases(self, like=None)

List existing databases in the current connection.

Parameters

Name Type Description Default
like str | None A pattern in Python’s regex format to filter returned database names. None

Returns

Type Description
list[str] The database names that exist in the current connection, that match the like pattern if provided.

list_schemas

list_schemas(self, like=None, database=None)

list_tables

list_tables(self, like=None, database=None, schema=None)

List the tables in the database.

Parameters

Name Type Description Default
like str | None A pattern to use for listing tables. None
database str | None The database (catalog) to perform the list against. None
schema str | None The schema inside database to perform the list against. ::: {.callout-warning} ## schema refers to database hierarchy The schema parameter does not refer to the column names and types of table. ::: None

raw_sql

raw_sql(self, query)

Execute a query and return the cursor used for execution.

Consider using .sql instead

If your query is a SELECT statement you can use the backend .sql method to avoid having to manually release the cursor returned from this method.

The cursor returned from this method must be manually released

You do not need to call .close() on the cursor when running DDL or DML statements like CREATE, INSERT or DROP, only when using SELECT statements.

To release a cursor, call the close method on the returned cursor object.

You can close the cursor by explicitly calling its close method:

cursor = con.raw_sql("SELECT ...")
cursor.close()

Or you can use a context manager:

with con.raw_sql("SELECT ...") as cursor:
    ...

Parameters

Name Type Description Default
query str | sqlalchemy.sqlalchemy.sql.sqlalchemy.sql.ClauseElement SQL query or SQLAlchemy expression to execute required

Examples

>>> con = ibis.connect("duckdb://")
>>> with con.raw_sql("SELECT 1") as cursor:
...     result = cursor.fetchall()
>>> result
[(1,)]
>>> cursor.closed
True

read_csv

read_csv(self, path, table_name=None, **kwargs)

Register a CSV file as a table in the Snowflake backend.

Parameters

Name Type Description Default
path str | pathlib.Path A string or Path to a CSV file; globs are supported required
table_name str | None Optional name for the table; if not passed, a random name will be generated None
kwargs typing.Any Snowflake-specific file format configuration arguments. See the documentation for the full list of options: https://docs.snowflake.com/en/sql-reference/sql/create-file-format#type-csv {}

Returns

Type Description
Table The table that was read from the CSV file

read_delta

read_delta(self, source, table_name=None, **kwargs)

Register a Delta Lake table in the current database.

Parameters

Name Type Description Default
source str | pathlib.Path The data source. Must be a directory containing a Delta Lake table. required
table_name str | None An optional name to use for the created table. This defaults to a sequentially generated name. None
**kwargs typing.Any Additional keyword arguments passed to the underlying backend or library. {}

Returns

Type Description
ibis.ibis.Table The just-registered table.

read_json

read_json(self, path, table_name=None, **kwargs)

Read newline-delimited JSON into an ibis table, using Snowflake.

Parameters

Name Type Description Default
path str | pathlib.Path A string or Path to a JSON file; globs are supported required
table_name str | None Optional table name None
kwargs typing.Any Additional keyword arguments. See https://docs.snowflake.com/en/sql-reference/sql/create-file-format#type-json for the full list of options. {}

Returns

Type Description
Table An ibis table expression

read_parquet

read_parquet(self, path, table_name=None, **kwargs)

Read a Parquet file into an ibis table, using Snowflake.

Parameters

Name Type Description Default
path str | pathlib.Path A string or Path to a Parquet file; globs are supported required
table_name str | None Optional table name None
kwargs typing.Any Additional keyword arguments. See https://docs.snowflake.com/en/sql-reference/sql/create-file-format#type-parquet for the full list of options. {}

Returns

Type Description
Table An ibis table expression

reconnect

reconnect(self)

Reconnect to the database already configured with connect.

register_options

register_options(cls)

Register custom backend options.

rename_table

rename_table(self, old_name, new_name)

Rename an existing table.

Parameters

Name Type Description Default
old_name str The old name of the table. required
new_name str The new name of the table. required

schema

schema(self, name)

Get an ibis schema from the current database for the table name.

Parameters

Name Type Description Default
name str Table name required

Returns

Type Description
Schema The ibis schema of name

sql

sql(self, query, schema=None, dialect=None)

Convert a SQL query to an Ibis table expression.

Parameters

Name Type Description Default
query str SQL string required
schema ibis.ibis.Schema | None The expected schema for this query. If not provided, will be inferred automatically if possible. None
dialect str | None Optional string indicating the dialect of query. The default value of None will use the backend’s native dialect. None

Returns

Type Description
Table Table expression

table

table(self, name, database=None, schema=None)

Create a table expression from a table in the database.

Parameters

Name Type Description Default
name str Table name required
database str | None The database the table resides in None
schema str | None The schema inside database where the table resides. ::: {.callout-warning} ## schema refers to database hierarchy The schema parameter does not refer to the column names and types of table. ::: None

Returns

Type Description
Table Table expression

to_csv

to_csv(self, expr, path, *, params=None, **kwargs)

Write the results of executing the given expression to a CSV file.

This method is eager and will execute the associated expression immediately.

Parameters

Name Type Description Default
expr ibis.ibis.Table The ibis expression to execute and persist to CSV. required
path str | pathlib.Path The data source. A string or Path to the CSV file. required
params collections.abc.Mapping[ibis.ibis.Scalar, typing.Any] | None Mapping of scalar parameter expressions to value. None
kwargs typing.Any Additional keyword arguments passed to pyarrow.csv.CSVWriter {}
https required

to_delta

to_delta(self, expr, path, *, params=None, **kwargs)

Write the results of executing the given expression to a Delta Lake table.

This method is eager and will execute the associated expression immediately.

Parameters

Name Type Description Default
expr ibis.ibis.Table The ibis expression to execute and persist to Delta Lake table. required
path str | pathlib.Path The data source. A string or Path to the Delta Lake table. required
params collections.abc.Mapping[ibis.ibis.Scalar, typing.Any] | None Mapping of scalar parameter expressions to value. None
kwargs typing.Any Additional keyword arguments passed to deltalake.writer.write_deltalake method {}

to_pandas

to_pandas(self, expr, *, params=None, limit=None, **kwargs)

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

Note

This method is a wrapper around execute.

Parameters

Name Type Description Default
expr ibis.ibis.Expr Ibis expression to execute. required
params collections.abc.Mapping[ibis.ibis.Scalar, typing.Any] | None Mapping of scalar parameter expressions to value. None
limit int | str | None An integer to effect a specific row limit. A value of None means “no limit”. The default is in ibis/config.py. None
kwargs typing.Any Keyword arguments {}

to_pandas_batches

to_pandas_batches(self, expr, *, params=None, limit=None, **_)

Execute an Ibis expression and return an iterator of pandas DataFrames.

Parameters

Name Type Description Default
expr ibis.ibis.Expr Ibis expression to execute. required
params collections.abc.Mapping[ibis.ibis.Scalar, typing.Any] | None Mapping of scalar parameter expressions to value. None
limit int | str | None An integer to effect a specific row limit. A value of None means “no limit”. The default is in ibis/config.py. None
chunk_size int Maximum number of rows in each returned DataFrame batch. This may have no effect depending on the backend. 1000000
kwargs typing.Any Keyword arguments {}

Returns

Type Description
collections.abc.Iterator[pandas.pandas.DataFrame] An iterator of pandas DataFrames.

to_parquet

to_parquet(self, expr, path, *, params=None, **kwargs)

Write the results of executing the given expression to a parquet file.

This method is eager and will execute the associated expression immediately.

Parameters

Name Type Description Default
expr ibis.ibis.Table The ibis expression to execute and persist to parquet. required
path str | pathlib.Path The data source. A string or Path to the parquet file. required
params collections.abc.Mapping[ibis.ibis.Scalar, typing.Any] | None Mapping of scalar parameter expressions to value. None
**kwargs typing.Any Additional keyword arguments passed to pyarrow.parquet.ParquetWriter {}
https required

to_pyarrow

to_pyarrow(self, expr, *, params=None, limit=None, **_)

Execute expression and return results in as a pyarrow table.

This method is eager and will execute the associated expression immediately.

Parameters

Name Type Description Default
expr ibis.ibis.Expr Ibis expression to export to pyarrow required
params collections.abc.Mapping[ibis.ibis.Scalar, typing.Any] | None Mapping of scalar parameter expressions to value. None
limit int | str | None An integer to effect a specific row limit. A value of None means “no limit”. The default is in ibis/config.py. None
kwargs typing.Any Keyword arguments {}

Returns

Type Description
Table A pyarrow table holding the results of the executed expression.

to_pyarrow_batches

to_pyarrow_batches(self, expr, *, params=None, limit=None, chunk_size=1000000, **_)

Execute expression and return an iterator of pyarrow record batches.

This method is eager and will execute the associated expression immediately.

Parameters

Name Type Description Default
expr ibis.ibis.Expr Ibis expression to export to pyarrow required
limit int | str | None An integer to effect a specific row limit. A value of None means “no limit”. The default is in ibis/config.py. None
params collections.abc.Mapping[ibis.ibis.Scalar, typing.Any] | None Mapping of scalar parameter expressions to value. None
chunk_size int Maximum number of rows in each returned record batch. 1000000

Returns

Type Description
RecordBatchReader Collection of pyarrow RecordBatchs.

to_torch

to_torch(self, expr, *, params=None, limit=None, **kwargs)

Execute an expression and return results as a dictionary of torch tensors.

Parameters

Name Type Description Default
expr ibis.ibis.Expr Ibis expression to execute. required
params collections.abc.Mapping[ibis.ibis.Scalar, typing.Any] | None Parameters to substitute into the expression. None
limit int | str | None An integer to effect a specific row limit. A value of None means no limit. None
kwargs typing.Any Keyword arguments passed into the backend’s to_torch implementation. {}

Returns

Type Description
dict[str, torch.torch.Tensor] A dictionary of torch tensors, keyed by column name.

truncate_table

truncate_table(self, name, database=None)

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