If an error occurs in a database trigger block, the AVM undoes the trigger block and returns ERROR.

If you use the NO-ERROR option on statements within a block, you are suppressing not only the visible error message but also the ERROR condition itself. Therefore, if you do this, it becomes your responsibility to check for errors and respond to them correctly. This might include issuing an UNDO statement of your own. The ON phrase in the header simply changes the default action for untrapped conditions.