Question

Is it possible to build a stored procedure that creates a trigger in MySQL?
I have the stored proc below, which works fine, but it only outputs the code to create the trigger, but does not actually create it.

DELIMITER $
CREATE PROCEDURE addCustomerLogTrigger()
BEGIN
    SELECT CONCAT(
        'CREATE TRIGGER customer_audit AFTER UPDATE ON customer FOR EACH ROW BEGIN ',
        GROUP_CONCAT(
            CONCAT(
                'IF OLD.', column_name, ' != NEW.', column_name, ' THEN INSERT INTO st_person_audit_log (',
                    'id, ',
                    'fieldName, ',
                    'old_value, ',
                    'new_value, ',
                    'time_stamp, ',
                    'person_id'
                    ') VALUES (
                    NEW.id,
                    ''', column_name, ''', 
                    OLD.', column_name, ',
                    NEW.', column_name, ',
                    NOW(),
                    NEW.last_updated_by
                ); END IF;'
            )
            SEPARATOR ' '
            ), ' END;$'
        )
        FROM
            information_schema.columns
        WHERE
            table_schema = database()
            AND table_name = 'customer';

END$
DELIMITER ;

Is there a way to create it in one go?
I got it from http://thenoyes.com/littlenoise/?p=43 and adjusted it a little to my needs.

Just FYI, this trigger inserts a old/new value pair into an audit table, whenever something changes in the customer table.

Answer 1

No, it is not possible, even with MySQL prepared statements.