Javascript email validation

function email_validation{
var email_reg = /^([A-Za-z0-9_\-\.])+\@([A-Za-z0-9_\-\.])+\.([A-Za-z]{2,4})$/;
if(email_reg.test(email) == false){
showMessage('Invali email address!');
error = true;
}
}

Get Multiple Values in the select list using Javascript

function getMultipleSelectedValues(filed_name)
{
var selObj = document.getElementById(filed_name);
var selectedArray = new Array();
var countObj = selObj.options.length;
var arr_count = 0;
for(var i = 0 ; i < countObj ; i++)
if (selObj.options[i].selected) {
selectedArray[arr_count] = selObj.options[i].value;
arr_count++;
}
return selectedArray;
}

Create TRIGGER to back-up the old data

CREATE TRIGGER backup_feedback
BEFORE UPDATE ON feedbacks
FOR EACH ROW
BEGIN
IF OLD.feedback <> NEW.feedback THEN
INSERT INTO user_logs(tab_name,field_name,old_value,new_value) VALUES ('feedbacks','feedback',OLD.feedback,NEW.feedback);
END IF;
END;