Throw an error in a MySQL Trigger If I have a trigger before the update on a table, how can I throw an error that prevents the update on that table? Solution :  Here is one hack that may work. It isn't clean, but it looks like it might work: Essentially, you just try to update a column that doesn't exist.

Throw an error in a MySQL trigger If I have a trigger before the update on a table, how can I throw an error that prevents the update on that table? answer :  Here is one hack that may work. It isn't clean, but it looks like it might work: Essentially, you just try to update a column that doesn't exist. Source :http://stackoverflow.com/questions/24/throw-an-error-in-a-mysql-trigger