Add Event to schedule, but not to DB

I’ve tried this code to avoid Save action in server, but it isn’t working

scheduler.attachEvent("onBeforeUpdate", function (id, status, data) {
    //any custom code
    return false;

Thank you

onBeforeUpdate is triggered by the dataProcessor (it is nested in a scheduler object). The code should look like following:

scheduler.dataProcessor.attachEvent("onBeforeUpdate",function(id,status, data){ //any custom code return false; });