How Can I Update a MySQL Table After an INSERT Trigger Without Errors?

Triggers and Table Updates in MySQL

When attempting to update the same table after an INSERT operation using a trigger, users may encounter the error "Can't update table ACCOUNTS ... already used by the statement that invoked this trigger." This limitation stems from the restriction against modifying a table that is currently being used by the triggering statement.

To work around this issue, it is not possible to rely solely on triggers. Instead, a stored procedure should be created to handle both the INSERT and update actions within a single transaction. By manually committing the changes using the stored procedure, users can circumvent the constraint imposed by triggers.

Steps for Implementing a Stored Procedure Workaround:

1. Create a Stored Procedure:

CREATE PROCEDURE update_accounts_status(IN new_account_pk BIGINT) AS
BEGIN
    -- Insert new account
    INSERT INTO ACCOUNTS (user_id, edit_on, status)
    VALUES (?, ?, 'A');
    
    -- Update old account
    UPDATE ACCOUNTS SET status = 'E' WHERE pk = ?;
    
    -- Commit changes
    COMMIT;
END

2. Call the Stored Procedure:

Instead of using a trigger, the stored procedure can be called upon INSERT into the ACCOUNTS table. This ensures that both the insert and update actions are executed successfully and committed within a single transaction.

Advantages of Using a Stored Procedure:

• Avoids the limitation of updating the same table within a trigger.
• Allows for greater flexibility and control over the transaction.
• Facilitates the execution of multiple operations (e.g., insert and update) within a single transaction.

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