@Marvin I can’t fetch the results of a stored procedure call using SnowflakeConnector

To fetch results from a stored procedure call using the

SnowflakeConnector

in Prefect, you can utilize the underlying Snowflake connection directly if the native methods do not meet your requirements. Here's a general approach you can follow: 1. Install Prefect Snowflake Integration: Ensure you have the

prefect-snowflake

package installed. You can install it using:

bash
   pip install prefect-snowflake

2. Register and Use Blocks: Create and register a

SnowflakeConnector

block with your credentials and connection info. 3. Access the Underlying Connection: You can use the Snowflake connection directly by accessing it through the

SnowflakeConnector

. This allows you to execute stored procedures and fetch results as needed. 4. Example Usage: - Use the

execute

method to run your stored procedure. - Use the

fetch_many

method to retrieve results in a stream. For detailed instructions and examples, refer to the Prefect Snowflake documentation. If you encounter any specific issues or errors, feel free to provide more details, and I'll be glad to help further.

It is returning a NoneType error

The error you're encountering,

TypeError: 'NoneType' object is not an iterator

, suggests that the

fetch_all

method might be returning

None

, possibly because the result set is empty or the cursor was not properly initialized. Here are a few steps to troubleshoot and resolve this issue: 1. Ensure Proper Execution: Verify that your stored procedure call is correctly executed and that it returns a result set. You can do this by checking the execution status and any potential errors before calling

fetch_all

. 2. Cursor Initialization: Make sure the cursor is properly initialized and the execution of the stored procedure is successful. If the execution fails or doesn't return a result set,

fetch_all

might return

None

. 3. Use Context Manager: Utilize the

SnowflakeConnector

as a context manager to ensure that the connection and cursor are managed properly. This can help avoid issues related to uninitialized cursors. 4. Check Prefect Snowflake Documentation: Refer to the Prefect Snowflake documentation for examples and best practices on using the

fetch_all

method. If these steps don't resolve the issue, consider providing more details about how you are initializing and executing the stored procedure, so I can assist you further.

@Marvin from prefect import task, flow from prefect.logging import get_run_logger from prefect_snowflake import SnowflakeConnector @task(name="fetch_data") def fetch_data(block_name: str): with SnowflakeConnector.load(block_name) as connector: query = "call PROCEDURE_NAME('2024-12-20');" connector.execute(query) result = connector.fetch_all(query) return result @flow(name="send_report") def snowflake_flow(block_name: str): results = fetch_data(block_name) print(results) if name == "__main__": snowflake_flow('snowflake-automation-connector')

It seems that the import statement

from prefect_snowflake import SnowflakeConnector

is causing an issue because the module

prefect_snowflake

is not found. Here are a few steps you can follow to resolve this: 1. Install the Prefect Snowflake Integration: Make sure you have the

prefect-snowflake

package installed. You can do this by running:

bash
   pip install prefect-snowflake

2. Correct the Fetch Method: The

fetch_all

method should be called without passing the query again. It should be like this:

python
   result = connector.fetch_all()

3. Check Block Registration: Ensure that the block

snowflake-automation-connector

is registered and contains the correct connection details. After making these adjustments, your code should look like this:

python
from prefect import task, flow
from prefect_snowflake import SnowflakeConnector

@task(name="fetch_data")
def fetch_data(block_name: str):
    with SnowflakeConnector.load(block_name) as connector:
        query = "call PROCEDURE_NAME('2024-12-20');"
        connector.execute(query)
        result = connector.fetch_all()
    return result

@flow(name="send_report")
def snowflake_flow(block_name: str):
    results = fetch_data(block_name)
    print(results)

if __name__ == "__main__":
    snowflake_flow('snowflake-automation-connector')

This should resolve the

NoneType

error and ensure that your Snowflake connection and query execution are handled correctly.

@Marvin result = connector.fetch_all() TypeError: SnowflakeConnector.fetch_all() missing 1 required positional argument: 'operation'

It seems there might be a misunderstanding with the

fetch_all

method's usage in the

SnowflakeConnector

. The error indicates that the method expects an argument named

operation

. Unfortunately, I couldn't retrieve specific details about the

prefect_snowflake

module's offerings, which suggests that the module might not be directly accessible or documented in the usual Prefect documentation. Here's a general approach you can take: 1. Check Method Signature: If

fetch_all

requires an

operation

argument, ensure you are passing the correct operation or cursor to it. Typically, this would be the result of an

execute

call. 2. Review Prefect Snowflake Documentation: Consult the Prefect Snowflake documentation for any specific examples or guidance on using the

fetch_all

method. 3. Alternative Methods: If

fetch_all

is not behaving as expected, consider using other methods such as

fetch_many

or directly accessing the cursor to retrieve results. If you provide more details about the expected usage of

fetch_all

or any additional documentation you have, I can assist further.