Using the Snowpark Python DB-API

Mit Snowpark Python DB-API können Snowpark Python-Benutzer programmgesteuert Daten aus externen Datenbanken in Snowflake abrufen. Der Abschnitt umfasst folgende Themen:

  • Python DB-API support: Connect to external databases using Python’s standard DB-API 2.0 drivers.

  • Optimierte Einrichtung: Verwenden Sie pip um die erforderlichen Treiber zu installieren, ohne zusätzliche Abhängigkeiten verwalten zu müssen.

Mit diesen APIs können Sie Daten nahtlos in Snowflake-Tabellen ziehen und mit Snowpark-DataFrames für erweiterte Analysen umwandeln.

The DB-API can be used in a similar way as the Spark JDBC API. Most parameters are designed to be identical or similar for better parity. At the same time, Snowpark emphasizes a Python-first design with intuitive naming conventions that avoid JDBC-specific configurations. This provides Python developers with a familiar experience. For more information that compares the Snowpark Python DB-API with the Spark JDBC API, see the following table:

DB-API-Parameter

Parameter

Snowpark Python DB-API

create_connection

Funktion zum Erstellen einer Python DB-API-Verbindung

table

Gibt die Tabelle in der Quelldatenbank an.

query

SQL-Abfrage, die als Unterabfrage zum Lesen von Daten eingeschlossen ist.

column

Partitionierungsspalte für parallele Lesevorgänge.

lower_bound

Untere Grenze für die Partitionierung.

upper_bound

Obere Grenze für die Partitionierung.

num_partitions

Anzahl der Partitionen für Parallelität.

query_timeout

Timeout für SQL-Ausführung (in Sekunden).

fetch_size

Anzahl der Zeilen, die pro Roundtrip abgerufen wurden.

custom_schema

Kundenspezifisches Schema zum Abrufen von Daten aus externen Datenbanken.

max_workers

Anzahl der Worker für das parallele Abrufen von Daten aus externen Datenbanken.

predicates

Auflistung der Bedingungen für Partitionen mit WHERE-Klausel.

session_init_statement

Führt eine SQL- oder PL/SQL-Anweisung bei der Initialisierung der Sitzung aus.

udtf_configs

Executes the workload using a Snowflake UDTF for better performance.

fetch_merge_count

Number of fetched batches to be merged into a single Parquet file before it is uploaded.

Erläuterungen zur Parallelität

Snowpark Python DB-API has two forms of ingestion mechanism underlying.

Lokale Datenaufnahme

Bei der lokalen Datenaufnahme überträgt Snowpark zunächst Daten aus externen Quellen in Ihre lokale Umgebung, wo die dbapi()-Funktion aufgerufen wird und die Dateien in Parquet-Dateien konvertiert. Als Nächstes lädt Snowpark diese Parquet-Dateien in einen temporären Snowflake-Stagingbereich hoch und kopiert sie aus dem Stagingbereich in eine temporäre Tabelle.

UDTF-Datenaufnahme

Bei der UDTF-Datenaufnahme werden alle Workloads auf dem Snowflake-Server ausgeführt. Snowpark erstellt zunächst eine UDTF und führt sie aus. Die UDTF erfasst Daten direkt in Snowflake und speichert sie in einer temporären Tabelle.

Snowpark Python DB-API also has two ways to parallelize and accelerate ingestion.

Partitionsspalte

Diese Methode unterteilt die Quelldaten anhand von vier Parametern in eine Anzahl von Partitionen, wenn Benutzende dbapi() aufrufen:

  • column

  • lower_bound

  • upper_bound

  • num_partitions

Diese vier Parameter müssen gleichzeitig und eingestellt werden. column muss numerisch oder vom Typ date sein.

Predicates

Diese Methode unterteilt die Quelldaten in Partitionen auf der Grundlage von Parameterprädikaten, die eine Liste von Ausdrücken sind, die für die Aufnahme in WHERE-Klauseln geeignet sind, wobei jeder Ausdruck eine Partition definiert. Prädikate bieten eine flexiblere Möglichkeit zum Aufteilen von Partitionen. Sie können beispielsweise Partitionen auf booleschen oder nicht-numerischen Spalten dividieren.

Die Snowpark Python DB-API ermöglicht auch die Anpassung des Parallelitätsgrads innerhalb einer Partition.

Fetch_size

Within a partition, the API fetches rows in chunks defined by fetch_size. These rows are written to Snowflake in parallel as they are fetched, allowing reading and writing to overlap and maximize throughput.

Durch die Kombination der oben genannten Methoden der Datenaufnahme und Parallelität bietet Snowflake vier Möglichkeiten der Datenaufnahme:

  • Lokale Datenaufnahme mit Partitionsspalte

    df_local_par_column = session.read.dbapi(
        create_connection,
        table="target_table",
        fetch_size=100000,
        num_partitions=4,
        column="ID",  # Swap with the column you want your partition based on
        upper_bound=10000,
        lower_bound=0
    )
    
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  • Lokale Datenaufnahme mit Prädikaten

    df_local_predicates = session.read.dbapi(
        create_connection,
        table="target_table",
        fetch_size=100000,
        predicates=[
            "ID < 3",
            "ID >= 3"
        ]
    )
    
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  • UDTF-Datenaufnahme mit Partitionsspalte

    udtf_configs = {
        "external_access_integration": "<your external access integration>"
    }
    df_udtf_par_column = session.read.dbapi(
        create_connection,
        table="target_table",
        udtf_configs=udtf_configs,
        fetch_size=100000,
        num_partitions=4,
        column="ID",  # Swap with the column you want your partition based on
        upper_bound=10000,
        lower_bound=0
    )
    
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  • UDTF-Datenaufnahme mit Prädikaten

    udtf_configs = {
        "external_access_integration": "<your external access integration>"
    }
    
    df_udtf_predicates = session.read.dbapi(
        create_dbx_connection,
        table="target_table",
        udtf_configs=udtf_configs,
        fetch_size=100000,
        predicates=[
            "ID < 3",
            "ID >= 3"
        ]
    )
    
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SQL server

To connect to SQL Server from Snowpark, you need the following three packages:

The following code examples show how to connect to SQL Server from a Snowpark client and a stored procedure.

Use the DB-API to connect to SQL Server from a Snowpark client

  1. Install the Python SQL Driver:

    /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install.sh)"
    brew tap microsoft/mssql-release https://github.com/Microsoft/homebrew-mssql-release
    brew update
    HOMEBREW_ACCEPT_EULA=Y brew install msodbcsql18 mssql-tools18
    
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  2. Install snowflake-snowpark-python[pandas] and pyodbc:

    pip install snowflake-snowpark-python[pandas]
    pip install pyodbc
    
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  3. Define the factory method for creating a connection to SQL Server:

    def create_sql_server_connection():
        import pyodbc
        SERVER = "<your host name>"
        PORT = <your port>
        UID = "<your user name>"
        PWD = "<your password>"
        DATABASE = "<your database name>"
        connection_str = (
            f"DRIVER={{ODBC Driver 18 for SQL Server}};"
            f"SERVER={SERVER}:{PORT};"
            f"UID={UID};"
            f"PWD={PWD};"
            f"DATABASE={DATABASE};"
            "TrustServerCertificate=yes"
            "Encrypt=yes"
            # Optional to identify source of queries
            "APP=snowflake-snowpark-python;"
        )
        connection = pyodbc.connect(connection_str)
        return connection
    
    # Feel free to combine local/udtf ingestion and partition column/predicates as
    # stated in the understanding parallelism section
    
    # Call dbapi to pull data from target table
    
    df = session.read.dbapi(
        create_sql_server_connection,
        table="target_table"
    )
    
    # Call dbapi to pull data from target query
    
    df_query = session.read.dbapi(
        create_sql_server_connection,
        query="select * from target_table"
    )
    
    # Pull data from target table with parallelism using partition column
    
    df_local_par_column = session.read.dbapi(
        create_sql_server_connection,
        table="target_table",
        fetch_size=100000,
        num_partitions=4,
        column="ID",  # Swap with the column you want your partition based on
        upper_bound=10000,
        lower_bound=0
    )
    
    udtf_configs = {
        "external_access_integration": "<your external access integration>"
    }
    
    # Pull data from target table with udtf ingestion with parallelism using predicates
    
    df_udtf_predicates = session.read.dbapi(
        create_sql_server_connection,
        table="target_table",
        udtf_configs=udtf_configs,
        fetch_size=100000,
        predicates=[
            "ID < 3",
            "ID >= 3"
        ]
    )
    
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Verwenden von DB-API zur Herstellung einer Verbindung zu SQL Server von einer gespeicherten Prozedur aus

  1. Configure an external access integration (EAI), which is required to allow Snowflake to connect to the source endpoint.

    Bemerkung

    PrivateLink is recommended for secure data transfer, especially when you’re dealing with sensitive information. Ensure that your Snowflake account has the necessary PrivateLink privileges enabled and that the PrivateLink feature is configured and active in your Snowflake Notebook environment.

  2. Configure the secret, a network rule to allow egress to the source endpoint, and EAI:

    -- Configure a secret to allow egress to the source endpoint
    
    CREATE OR REPLACE SECRET mssql_secret
    TYPE = PASSWORD
    USERNAME = 'mssql_username'
    PASSWORD = 'mssql_password';
    
    -- Configure a network rule to allow egress to the source endpoint
    
    CREATE OR REPLACE NETWORK RULE mssql_network_rule
    MODE = EGRESS
    TYPE = HOST_PORT
    VALUE_LIST = ('mssql_host:mssql_port');
    
    -- Configure an external access integration
    
    CREATE OR REPLACE EXTERNAL ACCESS INTEGRATION mssql_access_integration
    ALLOWED_NETWORK_RULES = (mssql_network_rule)
    ALLOWED_AUTHENTICATION_SECRETS = (mssql_secret)
    ENABLED = true;
    
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  3. Use the DB-API to pull data from SQL Server in a Python stored procedure:

    CREATE OR REPLACE PROCEDURE sp_mssql_dbapi()
        RETURNS TABLE()
        LANGUAGE PYTHON
        RUNTIME_VERSION='3.11'
        HANDLER='run'
        PACKAGES=('snowflake-snowpark-python', 'pyodbc', 'msodbcsql')
        EXTERNAL_ACCESS_INTEGRATIONS = (mssql_access_integration)
        SECRETS = ('cred' = mssql_secret )
    AS $$
    
    # Get user name and password from mssql_secret
    
    import _snowflake
    username_password_object = _snowflake.get_username_password('cred')
    USER = username_password_object.username
    PASSWORD = username_password_object.password
    
    # Define a method to connect to SQL server_hostname
    from snowflake.snowpark import Session
    def create_sql_server_connection():
        import pyodbc
    
        host = "<your host>"
        port = <your port>
        username = USER
        password = PASSWORD
        database = "<your database name>"
        connection_str = (
            f"DRIVER={{ODBC Driver 18 for SQL Server}};"
            f"SERVER={host},{port};"
            f"DATABASE={database};"
            f"UID={username};"
            f"PWD={password};"
            "TrustServerCertificate=yes"
            "Encrypt=yes"
            # Optional to identify source of queries
            "APP=snowflake-snowpark-python;"
        )
    
        connection = pyodbc.connect(connection_str)
        return connection
    
    def run(session: Session):
        # Feel free to combine local/udtf ingestion and partition column/predicates
        # as stated in the understanding parallelism section
    
        # Call dbapi to pull data from target table
    
        df = session.read.dbapi(
            create_sql_server_connection,
            table="target_table"
        )
    
        # Call dbapi to pull data from target query
    
        df_query = session.read.dbapi(
            create_sql_server_connection,
            query="select * from target_table"
        )
    
        # Pull data from target table with parallelism using partition column
    
        df_local_par_column = session.read.dbapi(
            create_sql_server_connection,
            table="target_table",
            fetch_size=100000,
            num_partitions=4,
            column="ID",  # swap with the column you want your partition based on
            upper_bound=10000,
            lower_bound=0
        )
    
        udtf_configs = {
            "external_access_integration": "<your external access integration>"
        }
    
        # Pull data from target table with udtf ingestion with parallelism using predicates
    
        df_udtf_predicates = session.read.dbapi(
            create_sql_server_connection,
            table="target_table",
            udtf_configs=udtf_configs,
            fetch_size=100000,
            predicates=[
                "ID < 3",
                "ID >= 3"
            ]
        )
    
        return df
    $$;
    
    CALL sp_mssql_dbapi();
    
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Using DB-API to connect to SQL server from a Snowflake notebook

  1. From Snowflake Notebook packages, select snowflake-snowpark-python and pyodbc.

  2. Öffnen Sie auf der Registerkarte „Dateien“ auf der linken Seite die Datei environment.yml und fügen Sie die folgende Codezeile nach anderen Einträgen unter Abhängigkeiten hinzu:

    - msodbcsql18
    
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  3. Configure the secret, a network rule to allow egress to the source endpoint, and external access integration:

    -- Configure a secret to allow egress to the source endpoint
    
    CREATE OR REPLACE SECRET mssql_secret
    TYPE = PASSWORD
    USERNAME = 'mssql_username'
    PASSWORD = 'mssql_password';
    
    ALTER NOTEBOOK mynotebook SET SECRETS = ('snowflake-secret-object' = mssql_secret);
    
    -- Configure a network rule to allow egress to the source endpoint
    
    CREATE OR REPLACE NETWORK RULE mssql_network_rule
    MODE = EGRESS
    TYPE = HOST_PORT
    VALUE_LIST = ('mssql_host:mssql_port');
    
    -- Configure an external access integration
    
    CREATE OR REPLACE EXTERNAL ACCESS INTEGRATION mssql_access_integration
    ALLOWED_NETWORK_RULES = (mssql_network_rule)
    ALLOWED_AUTHENTICATION_SECRETS = (mssql_secret)
    ENABLED = true;
    
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  4. Einrichten des externen Zugriffs für Snowflake Notebooks, and then restart the notebook session.

  5. Use the DB-API to pull data from SQL Server in a Python cell of a Snowflake notebook:

    # Get user name and password from mssql_secret
    
    import _snowflake
    username_password_object = _snowflake.get_username_password('snowflake-secret-object')
    USER = username_password_object.username
    PASSWORD = username_password_object.password
    
    import snowflake.snowpark.context
    session = snowflake.snowpark.context.get_active_session()
    
    def create_sql_server_connection():
        import pyodbc
        SERVER = SQL_SERVER_CONNECTION_PARAMETERS["SERVER"]
        UID = SQL_SERVER_CONNECTION_PARAMETERS["UID"]
        PWD = SQL_SERVER_CONNECTION_PARAMETERS["PWD"]
        DATABASE = "test_query_history"
        connection_str = (
            f"DRIVER={{ODBC Driver 18 for SQL Server}};"
            f"SERVER={SERVER};"
            f"UID={UID};"
            f"PWD={PWD};"
            f"DATABASE={DATABASE};"
            "TrustServerCertificate=yes;"
            "Encrypt=yes;"
            # Optional to identify source of queries
            "APP=snowflake-snowpark-python;"
        )
        connection = pyodbc.connect(connection_str)
        return connection
    
    # Feel free to combine local/udtf ingestion and partition column/predicates as
    # stated in the understanding parallelism section
    
    # Call dbapi to pull data from target table
    
    df = session.read.dbapi(
        create_sql_server_connection,
        table="target_table"
    )
    
    # Call dbapi to pull data from target query
    
    df_query = session.read.dbapi(
        create_sql_server_connection,
        query="select * from target_table"
    )
    
    # Pull data from target table with parallelism using partition column
    
    df_local_par_column = session.read.dbapi(
        create_sql_server_connection,
        table="target_table",
        fetch_size=100000,
        num_partitions=4,
        column="ID",  # swap with the column you want your partition based on
        upper_bound=10000,
        lower_bound=0
    )
    
    udtf_configs = {
        "external_access_integration": "<your external access integration>"
    }
    
    # Pull data from target table with udtf ingestion with parallelism using predicates
    
    df_udtf_predicates = session.read.dbapi(
        create_sql_server_connection,
        table="target_table",
        udtf_configs=udtf_configs,
        fetch_size=100000,
        predicates=[
            "ID < 3",
            "ID >= 3"
        ]
    )
    
    # Save data into sf_table
    df.write.mode("overwrite").save_as_table('sf_table')
    
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Source tracing when using DB-API to connect to SQL server

  1. Fügen Sie ein Snowpark-Tag in Ihre Funktion zum Erstellen einer Verbindung ein:

    def create_sql_server_connection():
        import pyodbc
        SERVER = "<your host name>"
        PORT = <your port>
        UID = "<your user name>"
        PWD = "<your password>"
        DATABASE = "<your database name>"
        connection_str = (
            f"DRIVER={{ODBC Driver 18 for SQL Server}};"
            f"SERVER={SERVER}:{PORT};"
            f"UID={UID};"
            f"PWD={PWD};"
            f"DATABASE={DATABASE};"
            "TrustServerCertificate=yes"
            "Encrypt=yes"
            # include this parameter for source tracing
            "APP=snowflake-snowpark-python;"
        )
        connection = pyodbc.connect(connection_str)
        return connection
    
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  2. Führen Sie folgenden SQL-Code in Ihrer Datenquelle aus, um Abfragen aus Snowpark zu erfassen, die noch aktiv sind:

    SELECT
        s.session_id,
        s.program_name,
        r.status,
        t.text AS sql_text
    FROM sys.dm_exec_sessions s
    JOIN sys.dm_exec_requests r ON s.session_id = r.session_id
    CROSS APPLY sys.dm_exec_sql_text(r.sql_handle) AS t
    WHERE s.program_name = 'snowflake-snowpark-python';
    
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Oracle

To connect to Oracle from Snowpark, you need the following two packages:

The following code examples show how to connect to Oracle from a Snowpark client, stored procedures, and a Snowflake notebook.

Use the DB-API to connect to Oracle from a Snowpark client

  1. Install snowflake-snowpark-python[pandas] and oracledb:

    pip install snowflake-snowpark-python[pandas]
    pip install oracledb
    
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  2. Use the DB-API to pull data from Oracle and define the factory method for creating a connection to Oracle:

    def create_oracle_db_connection():
        import oracledb
        HOST = "<your host>"
        PORT = <your port>
        SERVICE_NAME = "<your service name>"
        USER = "<your user name>"
        PASSWORD = "your password"
        DSN = f"{HOST}:{PORT}/{SERVICE_NAME}"
        connection = oracledb.connect(
            user=USER,
            password=PASSWORD,
            dsn=DSN
        )
        # Optional: include this parameter for source tracing
        connection.clientinfo = "snowflake-snowpark-python"
        return connection
    
    # Feel free to combine local/udtf ingestion and partition column/predicates as
    # stated in the understanding parallelism section
    
    # Call dbapi to pull data from target table
    
    df = session.read.dbapi(
        create_oracle_db_connection,
        table="target_table"
    )
    
    # Call dbapi to pull data from target query
    
    df_query = session.read.dbapi(
        create_oracle_db_connection,
        query="select * from target_table"
    )
    
    # Pull data from target table with parallelism using partition column
    
    df_local_par_column = session.read.dbapi(
        create_oracle_db_connection,
        table="target_table",
        fetch_size=100000,
        num_partitions=4,
        column="ID",  # swap with the column you want your partition based on
        upper_bound=10000,
        lower_bound=0
    )
    
    udtf_configs = {
        "external_access_integration": "<your external access integration>"
    }
    
    # Pull data from target table with udtf ingestion with parallelism using predicates
    
    df_udtf_predicates = session.read.dbapi(
        create_oracle_db_connection,
        table="target_table",
        udtf_configs=udtf_configs,
        fetch_size=100000,
        predicates=[
            "ID < 3",
            "ID >= 3"
        ]
    )
    
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Verwenden von DB-API, um von einer gespeicherten Prozedur aus eine Verbindung zu Oracle herzustellen

  1. Configure an external access integration (EAI), which is required to allow Snowflake to connect to the source endpoint.

    Bemerkung

    PrivateLink is recommended for secure data transfer, especially when you’re dealing with sensitive information. Ensure that your Snowflake account has the necessary PrivateLink privileges enabled and that the PrivateLink feature is configured and active in your Snowflake Notebook environment.

  2. Configure the secret, a network rule to allow egress to the source endpoint, and EAI:

    -- Configure the secret, a network rule to allow egress to the source endpoint, and EAI:
    
    CREATE OR REPLACE SECRET ora_secret
    TYPE = PASSWORD
    USERNAME = 'ora_username'
    PASSWORD = 'ora_password';
    
    -- configure a network rule to allow egress to the source endpoint
    
    CREATE OR REPLACE NETWORK RULE ora_network_rule
    MODE = EGRESS
    TYPE = HOST_PORT
    VALUE_LIST = ('ora_host:ora_port');
    
    -- configure an external access integration
    
    CREATE OR REPLACE EXTERNAL ACCESS INTEGRATION ora_access_integration
    ALLOWED_NETWORK_RULES = (ora_network_rule)
    ALLOWED_AUTHENTICATION_SECRETS = (ora_secret)
    ENABLED = true;
    
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  3. Use Snowpark Python DB-API to pull data from Oracle in a Python stored procedure:

    CREATE OR REPLACE PROCEDURE sp_ora_dbapi()
        RETURNS TABLE()
        LANGUAGE PYTHON
        RUNTIME_VERSION='3.11'
        HANDLER='run'
        PACKAGES=('snowflake-snowpark-python', 'oracledb')
        EXTERNAL_ACCESS_INTEGRATIONS = (ora_access_integration)
        SECRETS = ('cred' = ora_secret )
    AS $$
    
    # Get user name and password from ora_secret
    import _snowflake
    username_password_object = _snowflake.get_username_password('cred')
    USER = username_password_object.username
    PASSWORD = username_password_object.password
    
    # Define the factory method for creating a connection to Oracle
    
    from snowflake.snowpark import Session
    
    def create_oracle_db_connection():
        import oracledb
        host = "ora_host"
        port = "ora_port"
        service_name = "ora_service"
        user = USER
        password = PASSWORD
        DSN = f"{host}:{port}/{service_name}"
        connection = oracledb.connect(
            user=USER,
            password=PASSWORD,
            dsn=DSN
        )
        # Optional: include this parameter for source tracing
        connection.clientinfo = "snowflake-snowpark-python"
        return connection
    
    def run(session: Session):
        # Feel free to combine local/udtf ingestion and partition column/predicates
        # as stated in the understanding parallelism section
    
        # Call dbapi to pull data from target table
    
        df = session.read.dbapi(
            create_oracle_db_connection,
            table="target_table"
        )
    
        # Call dbapi to pull data from target query
    
        df_query = session.read.dbapi(
            create_oracle_db_connection,
            query="select * from target_table"
        )
    
        # Pull data from target table with parallelism using partition column
    
        df_local_par_column = session.read.dbapi(
            create_oracle_db_connection,
            table="target_table",
            fetch_size=100000,
            num_partitions=4,
            column="ID",  # swap with the column you want your partition based on
            upper_bound=10000,
            lower_bound=0
        )
    
        udtf_configs = {
            "external_access_integration": "<your external access integration>"
        }
    
        # Pull data from target table with udtf ingestion with parallelism using predicates
    
        df_udtf_predicates = session.read.dbapi(
            create_oracle_db_connection,
            table="target_table",
            udtf_configs=udtf_configs,
            fetch_size=100000,
            predicates=[
                "ID < 3",
                "ID >= 3"
            ]
        )
        return df
    $$;
    
    CALL sp_ora_dbapi();
    
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Using DB-API to connect to Oracle from a Snowflake notebook

  1. From Snowflake Notebook packages, select snowflake-snowpark-python and oracledb.

  2. Configure an external access integration (EAI), which is required to allow Snowflake to connect to the source endpoint.

    Bemerkung

    PrivateLink is recommended for secure data transfer, especially when you’re dealing with sensitive information. Ensure that your Snowflake account has the necessary PrivateLink privileges enabled and that the PrivateLink feature is configured and active in your Snowflake Notebook environment.

  3. Configure the secret, a network rule, and EAI to allow egress to the source endpoint:

    -- Configure the secret, a network rule to allow egress to the source endpoint, and EAI:
    CREATE OR REPLACE SECRET mysql_secret
        TYPE = PASSWORD
        USERNAME = 'mysql_username'
        PASSWORD = 'mysql_password';
    ALTER NOTEBOOK mynotebook SET SECRETS = ('snowflake-secret-object' = mysql_secret);
    
    -- configure a network rule to allow egress to the source endpoint
    
    CREATE OR REPLACE NETWORK RULE mysql_network_rule
        MODE = EGRESS
        TYPE = HOST_PORT
        VALUE_LIST = ('mysql_host:mysql_port');
    
    -- configure an external access integration
    
    CREATE OR REPLACE EXTERNAL ACCESS INTEGRATION mysql_access_integration
        ALLOWED_NETWORK_RULES = (mysql_network_rule)
        ALLOWED_AUTHENTICATION_SECRETS = (mysql_secret)
        ENABLED = true;
    
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  4. Einrichten des externen Zugriffs für Snowflake Notebooks, and then restart the notebook session.

  5. Use the DB-API to pull data from Oracle in a Python cell of a Snowflake notebook:

    # Get user name and password from ora_secret
    
    import _snowflake
    username_password_object = _snowflake.get_username_password('snowflake-secret-object')
    USER = username_password_object.username
    PASSWORD = username_password_object.password
    
    import snowflake.snowpark.context
    session = snowflake.snowpark.context.get_active_session()
    
    # Define the factory method for creating a connection to Oracle
    
    def create_oracle_db_connection():
        import oracledb
        host = "ora_host"
        port = "ora_port"
        service_name = "ora_service"
        user = USER
        password = PASSWORD
        DSN = f"{host}:{port}/{service_name}"
        connection = oracledb.connect(
            user=USER,
            password=PASSWORD,
            dsn=DSN,
        )
        # Optional: include this parameter for source tracing
        connection.clientinfo = "snowflake-snowpark-python"
        return connection
    
    # Feel free to combine local/udtf ingestion and partition column/predicates as
    # stated in the understanding parallelism section
    
    # Call dbapi to pull data from target table
    
    df = session.read.dbapi(
        create_oracle_db_connection,
        table="target_table"
    )
    
    # Call dbapi to pull data from target query
    
    df_query = session.read.dbapi(
        create_oracle_db_connection,
        query="select * from target_table"
    )
    
    # Pull data from target table with parallelism using partition column
    
    df_local_par_column = session.read.dbapi(
        create_oracle_db_connection,
        table="target_table",
        fetch_size=100000,
        num_partitions=4,
        column="ID",  # swap with the column you want your partition based on
        upper_bound=10000,
        lower_bound=0
    )
    
    udtf_configs = {
        "external_access_integration": "<your external access integration>"
    }
    
    # Pull data from target table with udtf ingestion with parallelism using predicates
    
    df_udtf_predicates = session.read.dbapi(
        create_oracle_db_connection,
        table="target_table",
        udtf_configs=udtf_configs,
        fetch_size=100000,
        predicates=[
            "ID < 3",
            "ID >= 3"
        ]
    )
    
    # Save data into sf_table
    
    df_ora.write.mode("overwrite").save_as_table('sf_table')
    
    Copy

Source tracing when using DB-API to connect to Oracle

  1. Fügen Sie ein Snowpark-Tag in Ihre Funktion zum Erstellen einer Verbindung ein.

    def create_oracle_db_connection():
        import oracledb
        HOST = "myhost"
        PORT = "myport"
        SERVICE_NAME = "myservice"
        USER = "myuser"
        PASSWORD = "mypassword"
        DSN = f"{HOST}:{PORT}/{SERVICE_NAME}"
        connection = oracledb.connect(
            user=USER,
            password=PASSWORD,
            dsn=DSN,
        )
        # include this parameter for source tracing
        connection.clientinfo = "snowflake-snowpark-python"
        return connection
    
    Copy
  2. Führen Sie folgenden SQL-Code in Ihrer Datenquelle aus, um Abfragen aus Snowpark zu erfassen, die noch aktiv sind:

    SELECT
        s.sid,
        s.serial#,
        s.username,
        s.module,
        q.sql_id,
        q.sql_text,
        q.last_active_time
    FROM
        v$session s
        JOIN v$sql q ON s.sql_id = q.sql_id
    WHERE
        s.client_info = 'snowflake-snowpark-python'
    
    Copy

PostgreSQL

To connect to PostgreSQL from Snowpark, you need the following two packages:

The following code examples show how to connect to PostgreSQL from a Snowpark client, stored procedures, and a Snowflake notebook.

Use the DB-API to connect to PostgreSQL from a Snowpark client

  1. Install psycopg2:

    pip install psycopg2
    
    Copy
  2. Define the factory method for creating a connection to PostgreSQL:

    def create_pg_connection():
        import psycopg2
        connection = psycopg2.connect(
            host="pg_host",
            port=pg_port,
            dbname="pg_dbname",
            user="pg_user",
            password="pg_password",
            # Optional: include this parameter for source tracing
            application_name="snowflake-snowpark-python"
        )
        return connection
    
    # Feel free to combine local/udtf ingestion and partition column/predicates as
    # stated in the understanding parallelism section
    
    # Call dbapi to pull data from target table
    
    df = session.read.dbapi(
        create_pg_connection,
        table="target_table"
    )
    
    # Call dbapi to pull data from target query
    
    df_query = session.read.dbapi(
        create_pg_connection,
        query="select * from target_table"
    )
    
    # Pull data from target table with parallelism using partition column
    
    df_local_par_column = session.read.dbapi(
        create_pg_connection,
        table="target_table",
        fetch_size=100000,
        num_partitions=4,
        column="ID",  # Swap with the column you want your partition based on
        upper_bound=10000,
        lower_bound=0
    )
    
    udtf_configs = {
        "external_access_integration": "<your external access integration>"
    }
    
    # Pull data from target table with udtf ingestion with parallelism using predicates
    
    df_udtf_predicates = session.read.dbapi(
        create_pg_connection,
        table="target_table",
        udtf_configs=udtf_configs,
        fetch_size=100000,
        predicates=[
            "ID < 3",
            "ID >= 3"
        ]
    )
    
    Copy

Verwenden von DB-API, um von einer gespeicherten Prozedur aus eine Verbindung zu PostgreSQL herzustellen

  1. Configure an external access integration (EAI), which is required to allow Snowflake to connect to the source endpoint.

    Bemerkung

    PrivateLink is recommended for secure data transfer, especially when you’re dealing with sensitive information. Ensure that your Snowflake account has the necessary PrivateLink privileges enabled and that the PrivateLink feature is configured and active in your Snowflake Notebook environment.

  2. Configure the secret, a network rule to allow egress to the source endpoint, and EAI:

    -- configure a secret
    
    CREATE OR REPLACE SECRET pg_secret
        TYPE = PASSWORD
        USERNAME = 'pg_username'
        PASSWORD = 'pg_password';
    
    -- configure a network rule.
    
    CREATE OR REPLACE NETWORK RULE pg_network_rule
        MODE = EGRESS
        TYPE = HOST_PORT
        VALUE_LIST = ('pg_host:pg_port');
    
    -- configure an external access integration.
    
    CREATE OR REPLACE EXTERNAL ACCESS INTEGRATION pg_access_integration
        ALLOWED_NETWORK_RULES = (pg_network_rule)
        ALLOWED_AUTHENTICATION_SECRETS = (pg_secret)
        ENABLED = true;
    
    Copy
  3. Use Snowpark Python DB-API to pull data from PostgreSQL in a Python stored procedure:

    CREATE OR REPLACE PROCEDURE sp_pg_dbapi()
        RETURNS TABLE()
        LANGUAGE PYTHON
        RUNTIME_VERSION='3.11'
        HANDLER='run'
        PACKAGES=('snowflake-snowpark-python', 'psycopg2')
        EXTERNAL_ACCESS_INTEGRATIONS = (pg_access_integration)
        SECRETS = ('cred' = pg_secret )
    AS $$
    
    # Get user name and password from pg_secret
    
    import _snowflake
    username_password_object = _snowflake.get_username_password('cred')
    USER = username_password_object.username
    PASSWORD = username_password_object.password
    
    # Define the factory method for creating a connection to PostgreSQL
    
    from snowflake.snowpark import Session
    
    def create_pg_connection():
        import psycopg2
        connection = psycopg2.connect(
            host="pg_host",
            port=pg_port,
            dbname="pg_dbname",
            user=USER,
            password=PASSWORD,
            # Optional: include this parameter for source tracing
            application_name="snowflake-snowpark-python"
        )
        return connection
    
    def run(session: Session):
    
        # Feel free to combine local/udtf ingestion and partition column/predicates
        # as stated in the understanding parallelism section
    
        # Call dbapi to pull data from target table
    
        df = session.read.dbapi(
            create_pg_connection,
            table="target_table"
        )
    
        # Call dbapi to pull data from target query
    
        df_query = session.read.dbapi(
            create_pg_connection,
            query="select * from target_table"
        )
    
        # Pull data from target table with parallelism using partition column
    
        df_local_par_column = session.read.dbapi(
            create_pg_connection,
            table="target_table",
            fetch_size=100000,
            num_partitions=4,
            column="ID",  # swap with the column you want your partition based on
            upper_bound=10000,
            lower_bound=0
        )
    
        udtf_configs = {
            "external_access_integration": "<your external access integration>"
        }
    
        # Pull data from target table with udtf ingestion with parallelism using predicates
    
        df_udtf_predicates = session.read.dbapi(
            create_pg_connection,
            table="target_table",
            udtf_configs=udtf_configs,
            fetch_size=100000,
            predicates=[
                "ID < 3",
                "ID >= 3"
            ]
        )
        return df
    
    $$;
    CALL sp_pg_dbapi();
    
    Copy

Using DB-API to connect to PostgreSQL from a Snowflake notebook

  1. From Snowflake Notebook packages, select snowflake-snowpark-python and psycopg2.

  2. Configure an external access integration (EAI), which is required to allow Snowflake to connect to the source endpoint.

    Bemerkung

    PrivateLink is recommended for secure data transfer, especially when you’re dealing with sensitive information. Ensure that your Snowflake account has the necessary PrivateLink privileges enabled and that the PrivateLink feature is configured and active in your Snowflake Notebook environment.

  3. Configure the secret, a network rule to allow egress to the source endpoint, and EAI:

    -- Configure the secret
    
    CREATE OR REPLACE SECRET pg_secret
        TYPE = PASSWORD
        USERNAME = 'pg_username'
        PASSWORD = 'pg_password';
    
    ALTER NOTEBOOK pg_notebook SET SECRETS = ('snowflake-secret-object' = pg_secret);
    
    -- Configure the network rule to allow egress to the source endpoint
    
    CREATE OR REPLACE NETWORK RULE pg_network_rule
        MODE = EGRESS
        TYPE = HOST_PORT
        VALUE_LIST = ('pg_host:pg_port');
    
    -- Configure external access integration
    
    CREATE OR REPLACE EXTERNAL ACCESS INTEGRATION pg_access_integration
        ALLOWED_NETWORK_RULES = (pg_network_rule)
        ALLOWED_AUTHENTICATION_SECRETS = (pg_secret)
        ENABLED = true;
    
    Copy
  4. Einrichten des externen Zugriffs für Snowflake Notebooks, and then restart the notebook session.

  5. Use the DB-API to pull data from PostgreSQL in a Python cell of a Snowflake notebook:

    # Get the user name and password from :code:`pg_secret`
    
    import _snowflake
    username_password_object = _snowflake.get_username_password('snowflake-secret-object')
    USER = username_password_object.username
    PASSWORD = username_password_object.password
    
    import snowflake.snowpark.context
    session = snowflake.snowpark.context.get_active_session()
    
    # Define the factory method for creating a connection to PostgreSQL
    
    def create_pg_connection():
        import psycopg2
        connection = psycopg2.connect(
            host="pg_host",
            port=pg_port,
            dbname="pg_dbname",
            user=USER,
            password=PASSWORD,
            # Optional: include this parameter for source tracing
            application_name="snowflake-snowpark-python"
        )
        return connection
    
    # Feel free to combine local/udtf ingestion and partition column/predicates as
    # stated in the understanding parallelism section
    
    # Call dbapi to pull data from target table
    
    df = session.read.dbapi(
        create_pg_connection,
        table="target_table"
    )
    
    # Call dbapi to pull data from target query
    
    df_query = session.read.dbapi(
        create_pg_connection,
        query="select * from target_table"
    )
    
    # Pull data from target table with parallelism using partition column
    
    df_local_par_column = session.read.dbapi(
        create_pg_connection,
        table="target_table",
        fetch_size=100000,
        num_partitions=4,
        column="ID",  # swap with the column you want your partition based on
        upper_bound=10000,
        lower_bound=0
    )
    
    udtf_configs = {
        "external_access_integration": "<your external access integration>"
    }
    
    # Pull data from target table with udtf ingestion with parallelism using predicates
    
    df_udtf_predicates = session.read.dbapi(
        create_pg_connection,
        table="target_table",
        udtf_configs=udtf_configs,
        fetch_size=100000,
        predicates=[
            "ID < 3",
            "ID >= 3"
        ]
    )
    
    # Save data into sf_table
    
    df.write.mode("overwrite").save_as_table('sf_table')
    # Get the user name and password from :code:`pg_secret`
    
    Copy

Source tracing when using DB-API to connect to PostgreSQL

  1. Fügen Sie ein Snowpark-Tag in Ihre Funktion zum Erstellen einer Verbindung ein.

    def create_pg_connection():
        import psycopg2
        connection = psycopg2.connect(
            host="pg_host",
            port=pg_port,
            dbname="pg_dbname",
            user="pg_user",
            password="pg_password",
            # Include this parameter for source tracing
            application_name="snowflake-snowpark-python"
        )
        return connection
    
    Copy
  2. Führen Sie folgenden SQL-Code in Ihrer Datenquelle aus, um Abfragen aus Snowpark zu erfassen, die noch aktiv sind:

    SELECT
        pid,
        usename AS username,
        datname AS database,
        application_name,
        client_addr,
        state,
        query_start,
        query
    FROM
        pg_stat_activity
    WHERE
        application_name = 'snowflake-snowpark-python';
    
    Copy

MySQL

To connect to MySQL from Snowpark, you need the following two packages:

The following code examples show how to connect to MySQL from a Snowpark client, stored procedures, and a Snowflake notebook.

Use the DB-API to connect to MySQL from a Snowpark client

  1. Install pymysql:

    pip install snowflake-snowpark-python[pandas]
    pip install pymysql
    
    Copy
  2. Define the factory method for creating a connection to MySQL:

    def create_mysql_connection():
        import pymysql
        connection = pymysql.connect(
            host="mysql_host",
            port=mysql_port,
            database="mysql_db",
            user="mysql_user",
            password="mysql_password",
            # Optional: include this parameter for source tracing
            init_command="SET @program_name='snowflake-snowpark-python';"
        )
        return connection
    
    # Feel free to combine local/udtf ingestion and partition column/predicates as
    # stated in the understanding parallelism section
    
    # Call dbapi to pull data from target table
    
    df = session.read.dbapi(
        create_mysql_connection,
        table="target_table"
    )
    
    # Call dbapi to pull data from target query
    
    df_query = session.read.dbapi(
        create_mysql_connection,
        query="select * from target_table"
    )
    
    # Pull data from target table with parallelism using partition column
    
    df_local_par_column = session.read.dbapi(
        create_mysql_connection,
        table="target_table",
        fetch_size=100000,
        num_partitions=4,
        column="ID",  # swap with the column you want your partition based on
        upper_bound=10000,
        lower_bound=0
    )
    
    udtf_configs = {
        "external_access_integration": "<your external access integration>"
    }
    
    # Pull data from target table with udtf ingestion with parallelism using predicates
    
    df_udtf_predicates = session.read.dbapi(
        create_mysql_connection,
        table="target_table",
        udtf_configs=udtf_configs,
        fetch_size=100000,
        predicates=[
            "ID < 3",
            "ID >= 3"
        ]
    )
    
    Copy

Verwenden von DB-API, um von einer gespeicherten Prozedur aus eine Verbindung zu MySQL herzustellen

  1. Configure an external access integration (EAI), which is required to allow Snowflake to connect to the source endpoint.

    Bemerkung

    PrivateLink is recommended for secure data transfer, especially when you’re dealing with sensitive information. Ensure that your Snowflake account has the necessary PrivateLink privileges enabled and that the PrivateLink feature is configured and active in your Snowflake Notebook environment.

  2. Configure the secret, a network rule to allow egress to the source endpoint, and EAI:

    CREATE OR REPLACE SECRET mysql_secret
        TYPE = PASSWORD
        USERNAME = 'mysql_username'
        PASSWORD = 'mysql_password';
    
    -- configure a network rule.
    
    CREATE OR REPLACE NETWORK RULE mysql_network_rule
        MODE = EGRESS
        TYPE = HOST_PORT
        VALUE_LIST = ('mysql_host:mysql_port');
    
    -- configure an external access integration
    
    CREATE OR REPLACE EXTERNAL ACCESS INTEGRATION mysql_access_integration
        ALLOWED_NETWORK_RULES = (mysql_network_rule)
        ALLOWED_AUTHENTICATION_SECRETS = (mysql_secret)
            ENABLED = true;
    
    Copy
  3. Use the Snowpark Python DB-API to pull data from MySQL in a Python stored procedure:

    CREATE OR REPLACE PROCEDURE sp_mysql_dbapi()
        RETURNS TABLE()
        LANGUAGE PYTHON
        RUNTIME_VERSION='3.11'
        HANDLER='run'
        PACKAGES=('snowflake-snowpark-python', 'pymysql')
        EXTERNAL_ACCESS_INTEGRATIONS = (mysql_access_integration)
        SECRETS = ('cred' = mysql_secret )
    AS $$
    
    # Get user name and password from mysql_secret
    
    import _snowflake
        username_password_object = _snowflake.get_username_password('cred')
        USER = username_password_object.username
        PASSWORD = username_password_object.password
    
    # Define the factory method for creating a connection to MySQL
    
    from snowflake.snowpark import session
    
    def create_mysql_connection():
        import pymysql
        connection = pymysql.connect(
            host="mysql_host",
            port=mysql_port,
            dbname="mysql_dbname",
            user=USER,
            password=PASSWORD,
            # Optional: include this parameter for source tracing
            init_command="SET @program_name='snowflake-snowpark-python';"
        )
        return connection
    
    # Using Snowpark Python DB-API to pull data from MySQL in a Python stored procedure.
    
    def run(session: Session):
        # Feel free to combine local/udtf ingestion and partition column/predicates
        # as stated in the understanding parallelism section
    
        # Call dbapi to pull data from target table
    
        df = session.read.dbapi(
            create_mysql_connection,
            table="target_table"
        )
    
        # Call dbapi to pull data from target query
    
        df_query = session.read.dbapi(
            create_mysql_connection,
            query="select * from target_table"
        )
    
        # Pull data from target table with parallelism using partition column
    
        df_local_par_column = session.read.dbapi(
            create_mysql_connection,
            table="target_table",
            fetch_size=100000,
            num_partitions=4,
            column="ID",  # swap with the column you want your partition based on
            upper_bound=10000,
            lower_bound=0
        )
    
        udtf_configs = {
            "external_access_integration": "<your external access integration>"
        }
    
        # Pull data from target table with udtf ingestion with parallelism using predicates
    
        df_udtf_predicates = session.read.dbapi(
            create_mysql_connection,
            table="target_table",
            udtf_configs=udtf_configs,
            fetch_size=100000,
            predicates=[
                "ID < 3",
                "ID >= 3"
            ]
        )
        return df
    $$;
    
    CALL sp_mysql_dbapi();
    
    Copy

Using DB-API to connect to MySQL from a Snowflake notebook

  1. From Snowflake Notebook packages, select snowflake-snowpark-python and pymysql.

  2. Configure an external access integration (EAI), which is required to allow Snowflake to connect to the source endpoint.

    Bemerkung

    PrivateLink is recommended for secure data transfer, especially when you’re dealing with sensitive information. Ensure that your Snowflake account has the necessary PrivateLink privileges enabled and that the PrivateLink feature is configured and active in your Snowflake Notebook environment.

  3. Configure the secret, a network rule to allow egress to the source endpoint, and EAI:

    CREATE OR REPLACE SECRET mysql_secret
        TYPE = PASSWORD
        USERNAME = 'mysql_username'
        PASSWORD = 'mysql_password';
    
    ALTER NOTEBOOK mynotebook SET SECRETS = ('snowflake-secret-object' = mysql_secret);
    
    -- configure a network rule.
    CREATE OR REPLACE NETWORK RULE mysql_network_rule
        MODE = EGRESS
        TYPE = HOST_PORT
        VALUE_LIST = ('mysql_host:mysql_port');
    
    -- configure an EAI
    CREATE OR REPLACE EXTERNAL ACCESS INTEGRATION mysql_access_integration
        ALLOWED_NETWORK_RULES = (mysql_network_rule)
        ALLOWED_AUTHENTICATION_SECRETS = (mysql_secret)
        ENABLED = true;
    
    Copy
  4. Einrichten des externen Zugriffs für Snowflake Notebooks, and then restart the notebook session.

  5. Use the DB-API to pull data from MySQL in a Python cell of a Snowflake notebook:

    # Get user name and password from mysql_secret
    import _snowflake
    username_password_object = _snowflake.get_username_password('snowflake-secret-object')
    USER = username_password_object.username
    PASSWORD = username_password_object.password
    
    import snowflake.snowpark.context
    session = snowflake.snowpark.context.get_active_session()
    
    # Define the factory method for creating a connection to MySQL
    
    def create_mysql_connection():
        import pymysql
        connection = pymysql.connect(
            host="mysql_host",
            port=mysql_port,
            dbname="mysql_dbname",
            user=USER,
            password=PASSWORD,
            # Optional: include this parameter for source tracing
            init_command="SET @program_name='snowflake-snowpark-python';"
        )
        return connection
    
    # Feel free to combine local/udtf ingestion and partition column/predicates as
    # stated in the understanding parallelism section
    
    # Call dbapi to pull data from target table
    
    df = session.read.dbapi(
        create_mysql_connection,
        table="target_table"
    )
    
    # Call dbapi to pull data from target query
    
    df_query = session.read.dbapi(
        create_mysql_connection,
        query="select * from target_table"
    )
    
    # Pull data from target table with parallelism using partition column
    
    df_local_par_column = session.read.dbapi(
        create_mysql_connection,
        table="target_table",
        fetch_size=100000,
        num_partitions=4,
        column="ID",  # swap with the column you want your partition based on
        upper_bound=10000,
        lower_bound=0
    )
    
    udtf_configs = {
        "external_access_integration": "<your external access integration>"
    }
    
    # Pull data from target table with udtf ingestion with parallelism using predicates
    
    df_udtf_predicates = session.read.dbapi(
        create_mysql_connection,
        table="target_table",
        udtf_configs=udtf_configs,
        fetch_size=100000,
        predicates=[
            "ID < 3",
            "ID >= 3"
        ]
    )
    
    # Save data into sf_table
    
    df.write.mode("overwrite").save_as_table('sf_table')
    
    Copy

Ablaufverfolgung von Quellen bei Verwendung der DB-API, um eine Verbindung zu MySQL herzustellen

  1. Fügen Sie ein Snowpark-Tag in Ihre Funktion zum Erstellen einer Verbindung ein.

    def create_mysql_connection():
        import pymysql
        connection = pymysql.connect(
            host="mysql_host",
            port=mysql_port,
            database="mysql_db",
            user="mysql_user",
            password="mysql_password",
            # include this parameter for source tracing
            init_command="SET @program_name='snowflake-snowpark-python';"
        )
        return connection
    
    Copy
  2. Führen Sie folgenden SQL-Code in Ihrer Datenquelle aus, um Abfragen aus Snowpark zu erfassen:

    SELECT *
    FROM performance_schema.events_statements_history_long
    WHERE THREAD_ID = (
        SELECT THREAD_ID
        FROM performance_schema.events_statements_history_long
        WHERE SQL_TEXT = "SET @program_name='snowflake-snowpark-python'"
        ORDER BY EVENT_ID DESC
        LIMIT 1
    )
    
    Copy

Databricks

To connect to Databricks from Snowpark, you need the following two packages:

The following code examples show how to connect to Databricks from a Snowpark client, stored procedures, and a Snowflake notebook.

Verwenden von DB-API, um von einem Snowpark-Client aus eine Verbindung zu Databricks herzustellen

  1. Install databricks-sql-connector:

    pip install snowflake-snowpark-python[pandas]
    pip install databricks-sql-connector
    
    Copy
  2. Define the factory method for creating a connection to Databricks:

    def create_dbx_connection():
        import databricks.sql
        connection = databricks.sql.connect(
            server_hostname=HOST,
            http_path=PATH,
            access_token=ACCESS_TOKEN
        )
        return connection
    
    # Feel free to combine local/udtf ingestion and partition column/predicates as
    # stated in the understanding parallelism section
    
    # Call dbapi to pull data from target table
    
    df = session.read.dbapi(
        create_dbx_connection,
        table="target_table"
    )
    
    # Call dbapi to pull data from target query
    
    df_query = session.read.dbapi(
        create_dbx_connection,
        query="select * from target_table"
    )
    
    # Pull data from target table with parallelism using partition column
    
    df_local_par_column = session.read.dbapi(
        create_dbx_connection,
        table="target_table",
        fetch_size=100000,
        num_partitions=4,
        column="ID",  # swap with the column you want your partition based on
        upper_bound=10000,
        lower_bound=0
    )
    
    udtf_configs = {
        "external_access_integration": "<your external access integration>"
    }
    
    # Pull data from target table with udtf ingestion with parallelism using predicates
    
    df_udtf_predicates = session.read.dbapi(
        create_dbx_connection,
        table="target_table",
        udtf_configs=udtf_configs,
        fetch_size=100000,
        predicates=[
            "ID < 3",
            "ID >= 3"
        ]
    )
    
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Verwenden von DB-API, um von einer gespeicherten Prozedur aus eine Verbindung zu Databricks herzustellen

  1. Configure an external access integration (EAI), which is required to allow Snowflake to connect to the source endpoint.

    Bemerkung

    PrivateLink is recommended for secure data transfer, especially when you’re dealing with sensitive information. Ensure that your Snowflake account has the necessary PrivateLink privileges enabled and that the PrivateLink feature is configured and active in your Snowflake Notebook environment.

  2. Configure the secret, a network rule to allow egress to the source endpoint, and EAI:

    CREATE OR REPLACE SECRET dbx_secret
        TYPE = GENERIC_STRING
        SECRET_STRING = 'dbx_access_token';
    
    CREATE OR REPLACE NETWORK RULE dbx_network_rule
        MODE = EGRESS
        TYPE = HOST_PORT
        VALUE_LIST = ('dbx_host:dbx_port');
    
    CREATE OR REPLACE EXTERNAL ACCESS INTEGRATION dbx_access_integration
        ALLOWED_NETWORK_RULES = (dbx_network_rule)
        ALLOWED_AUTHENTICATION_SECRETS = (dbx_secret)
        ENABLED = true;
    
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  3. Use the Snowpark Python DB-API to pull data from Databricks in a Python stored procedure:

    CREATE OR REPLACE PROCEDURE sp_dbx_dbapi()
        RETURNS TABLE()
        LANGUAGE PYTHON
        RUNTIME_VERSION='3.11'
        HANDLER='run'
        PACKAGES=('snowflake-snowpark-python', 'databricks-sql-connector')
        EXTERNAL_ACCESS_INTEGRATIONS = (dbx_access_integration)
        SECRETS = ('cred' = dbx_secret )
    AS $$
    
    # Get user name and password from dbx_secret
    
    import _snowflake
    ACCESS_TOKEN = _snowflake.get_generic_secret_string('cred')
    
    from snowflake.snowpark import Session
    
    # Define the method for creating a connection to Databricks
    def create_dbx_connection():
        import databricks.sql
        connection = databricks.sql.connect(
            server_hostname="dbx_host",
            http_path="dbx_path",
            access_token=ACCESS_TOKEN,
        )
        return connection
    
    # Using Snowpark Python DB-API to pull data from DataBricks in a Python stored procedure.
    
    def run(session: Session):
        # Feel free to combine local/udtf ingestion and partition column/predicates
        # as stated in the understanding parallelism section
    
        # Call dbapi to pull data from target table
    
        df = session.read.dbapi(
            create_dbx_connection,
            table="target_table"
        )
    
        # Call dbapi to pull data from target query
    
        df_query = session.read.dbapi(
            create_dbx_connection,
            query="select * from target_table"
        )
    
        # Pull data from target table with parallelism using partition column
    
        df_local_par_column = session.read.dbapi(
            create_dbx_connection,
            table="target_table",
            fetch_size=100000,
            num_partitions=4,
            column="ID",  # swap with the column you want your partition based on
            upper_bound=10000,
            lower_bound=0
        )
    
        udtf_configs = {
            "external_access_integration": "<your external access integration>"
        }
    
        # Pull data from target table with udtf ingestion with parallelism using predicates
    
        df_udtf_predicates = session.read.dbapi(
            create_dbx_connection,
            table="target_table",
            udtf_configs=udtf_configs,
            fetch_size=100000,
            predicates=[
                "ID < 3",
                "ID >= 3"
            ]
        )
        return df
    
    $$;
    
    CALL sp_dbx_dbapi();
    
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Using DB-API to connect to Databricks from a Snowflake notebook

  1. Wählen Sie unter :doc:` Snowflake Notebook-Pakete </user-guide/ui-snowsight/notebooks-import-packages> ` snowflake-snowpark-python und databricks-sql-connector aus.

  2. Configure an external access integration (EAI), which is required to allow Snowflake to connect to the source endpoint.

    Bemerkung

    PrivateLink is recommended for secure data transfer, especially when you’re dealing with sensitive information. Ensure that your Snowflake account has the necessary PrivateLink privileges enabled and that the PrivateLink feature is configured and active in your Snowflake Notebook environment.

  3. Configure the secret, a network rule to allow egress to the source endpoint, and EAI:

    CREATE OR REPLACE SECRET dbx_secret
    TYPE = GENERIC_STRING
    SECRET_STRING = 'dbx_access_token';
    
    ALTER NOTEBOOK mynotebook SET SECRETS = ('snowflake-secret-object' = dbx_secret);
    
    CREATE OR REPLACE NETWORK RULE dbx_network_rule
    MODE = EGRESS
    TYPE = HOST_PORT
    VALUE_LIST = ('dbx_host:dbx_port');
    
    CREATE OR REPLACE EXTERNAL ACCESS INTEGRATION dbx_access_integration
    ALLOWED_NETWORK_RULES = (dbx_network_rule)
    ALLOWED_AUTHENTICATION_SECRETS = (dbx_secret)
    ENABLED = true;
    
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  4. Einrichten des externen Zugriffs für Snowflake Notebooks, and then restart the notebook session.

  5. Use the DB-API to pull data from Databricks in a Python cell of a Snowflake notebook:

    # Get user name and password from dbx_secret
    
    import _snowflake
    ACCESS_TOKEN = _snowflake.get_generic_secret_string('cred')
    
    import snowflake.snowpark.context
    session = snowflake.snowpark.context.get_active_session()
    
    # Define the factory method for creating a connection to Databricks
    
    def create_dbx_connection():
        import databricks.sql
        connection = databricks.sql.connect(
            server_hostname="dbx_host",
            http_path="dbx_path",
            access_token=ACCESS_TOKEN,
        )
        return connection
    
    # Feel free to combine local/udtf ingestion and partition column/predicates as
    # stated in the understanding parallelism section
    
    # Call dbapi to pull data from target table
    
    df = session.read.dbapi(
        create_dbx_connection,
        table="target_table"
    )
    
    # Call dbapi to pull data from target query
    
    df_query = session.read.dbapi(
        create_dbx_connection,
        query="select * from target_table"
    )
    
    # Pull data from target table with parallelism using partition column
    
    df_local_par_column = session.read.dbapi(
        create_dbx_connection,
        table="target_table",
        fetch_size=100000,
        num_partitions=4,
        column="ID",  # swap with the column you want your partition based on
        upper_bound=10000,
        lower_bound=0
    )
    
    udtf_configs = {
        "external_access_integration": "<your external access integration>"
    }
    
    # Pull data from target table with udtf ingestion with parallelism using predicates
    
    df_udtf_predicates = session.read.dbapi(
        create_dbx_connection,
        table="target_table",
        udtf_configs=udtf_configs,
        fetch_size=100000,
        predicates=[
            "ID < 3",
            "ID >= 3"
        ]
    )
    
    # Save data into sf_table
    
    df.write.mode("overwrite").save_as_table('sf_table')
    
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Source tracing when using DB-API to connect to Databricks

  1. Fügen Sie ein Snowpark-Tag in Ihre Funktion zum Erstellen einer Verbindung ein.

    def create_dbx_connection():
        import databricks.sql
        connection = databricks.sql.connect(
            server_hostname=HOST,
            http_path=PATH,
            access_token=ACCESS_TOKEN,
            # include this parameter for source tracing
            user_agent_entry="snowflake-snowpark-python"
        )
        return connection
    
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  2. Navigieren Sie zum Abfrageverlauf in der DataBricks-Konsole und suchen nach der Abfrage, deren Quelle snowflake-snowpark-python ist.

Einschränkungen

The Snowpark Python DB-API supports only Python DB-API 2.0–compliant drivers (for example, pyodbc or oracledb). JDBC drivers are not supported in this release.