CASCADE DELETE just once

📝 Title: "Unlock the Power of CASCADE DELETE in Postgresql: A One-Time Solution"

Introduction: 👋 Hey there tech enthusiasts! Are you facing a situation where you need to perform a cascading delete in your Postgresql database, but the tables don't have the ON DELETE CASCADE rule set up? 😰 Don't worry, we've got you covered! In this blog post, we'll explore easy solutions to perform a one-time CASCADE DELETE in Postgresql. Let's dive in! 💪

Understanding the Problem: 🤔 So, you want to perform a cascading delete just once in your Postgresql database, without having the ON DELETE CASCADE rule set up for the tables. You might have come across an older question on Stack Overflow, where it seems like there is no straightforward solution. However, we're here to tell you that there is a way!

Solution: The Temporary Trigger Technique: 💡 One solution to perform a one-time CASCADE DELETE is by using a temporary trigger. Let's break down the steps:

Step 1️⃣: Create a Temporary Trigger Function: First, create a temporary trigger function that will handle the cascading delete logic. Here's an example:

CREATE OR REPLACE FUNCTION temp_cascade_delete()
RETURNS TRIGGER AS $$
BEGIN
    -- Cascade delete logic here
    DELETE FROM related_table WHERE foreign_key_column = OLD.primary_key_column;
    RETURN OLD;
END;
$$ LANGUAGE plpgsql;

Step 2️⃣: Attach the Temporary Trigger: Now, attach the temporary trigger to the table from which you want to perform the cascading delete. Use the AFTER DELETE trigger to ensure it runs after the delete operation. Here's an example:

CREATE TRIGGER temp_cascade_trigger
AFTER DELETE ON some_table
FOR EACH ROW
EXECUTE FUNCTION temp_cascade_delete();

Step 3️⃣: Perform the Cascading Delete: Finally, perform the delete operation on the table. The temporary trigger will take care of the cascading delete for you, just this once. 😊

DELETE FROM some_table;

Voila! 🎉 You have successfully performed a one-time CASCADE DELETE in Postgresql!

Call-to-Action: 🔥 We hope this guide helped you overcome the challenge of performing a cascading delete without the ON DELETE CASCADE rule in Postgresql. Share this post with your fellow developers who might be struggling with the same issue. Also, feel free to leave a comment below if you have any questions or want to share your experience. Let's help each other grow in the world of tech! 🚀