Automating Stored Procedure Execution in Snowflake with Non-Cron Tasks

Introduction to Snowflake Tasks and Non-Cron Scheduling

Snowflake offers a robust set of features for data processing, one of which is Tasks. Tasks allow developers to automate the execution of SQL statements and stored procedures. Unlike traditional cron jobs, Snowflake Tasks support non-cron scheduling, enabling more flexible and scalable automation. This guide walks you through using Snowflake Tasks to schedule stored procedures efficiently with a step-by-step demonstration.

Understanding the Basics and Purpose

Snowflake Tasks: Designed to automate execution within Snowflake, tasks are ideal for running SQL statements or calling stored procedures at defined intervals.
Non-Cron Scheduling: Snowflake provides an intuitive syntax to define intervals, bypassing the complexity of cron expressions. This is especially useful for scenarios requiring specific intervals or dependencies.

Creating a Sample Table and Stored Procedure

Before diving into tasks, let’s create a sample environment.

Sample Table

CREATE OR REPLACE TABLE sample_data (

id INT AUTOINCREMENT,

processed_at TIMESTAMP

);

Sample Stored Procedure

CREATE OR REPLACE PROCEDURE task_scenario()

RETURNS STRING

LANGUAGE SQL

BEGIN

INSERT INTO sample_data (processed_at)

VALUES (CURRENT_TIMESTAMP);

RETURN ‘Task executed successfully’;

END;

$$;

Setting Up the Environment for Task Demonstration

Ensure that you have:

A Snowflake account with proper role permissions.
A sample table and stored procedure are ready for demonstration.
The task warehouse is created or allocated for execution.

Crafting a Non-Cron Task for Scheduled Execution

Step-by-Step Creation and Activation

Create the Task

CREATE OR REPLACE TASK sample_task

WAREHOUSE = ‘TASK_WAREHOUSE’

SCHEDULE = ‘5 MINUTE’

CALL task_scenario();

Activate the Task

ALTER TASK sample_task RESUME;

Verify Task Status

SHOW TASKS LIKE ‘sample_task’;

Activating and Monitoring the Task

Monitoring Task Execution

Use Snowflake’s Task History to review execution logs:

SELECT * FROM TABLE(INFORMATION_SCHEMA.TASK_HISTORY());

Checking Initial Results

Verify if the stored procedure is executed by querying the table:

SELECT * FROM sample_data ORDER BY processed_at DESC;

Suspending the Task: Saving on Compute Charges

When not needed, suspend the task to save compute resources:

ALTER TASK sample_task SUSPEND;

Best Practices for Task Management

Use Dedicated Warehouses: Avoid overloading your primary warehouse.
Monitor Regularly: Review logs and metrics to ensure tasks run as expected.
Optimize Stored Procedures: Keep them efficient to minimize resource usage.
Avoid Overlapping Schedules: Ensure tasks don’t conflict to avoid race conditions.

Looking Ahead: Creating Task Dependencies

Snowflake allows tasks to trigger others, enabling complex workflows.

Example of Task Dependency

CREATE OR REPLACE TASK dependent_task

AFTER sample_task