How can I receive an e-mail when my MySQL table is updated?

Question

Hi I was wondering if there was a way in MySQL to automatically send an e-mail to myself whenever there is a row added to a MySQL table?

Answer 1

The best way to achieve this would be using a trigger and a cron. Create a 'notification queue' table and populate that with a trigger when a row is inserted in the desired table.

eg.

CREATE TABLE `notification_queue` (
  `notification_id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `sent` tinyint(1) unsigned NOT NULL,
  PRIMARY KEY (`notification_id`)
);

Then define a simple trigger:

DELIMITER $$
CREATE TRIGGER t_notification_insert 
AFTER INSERT ON [table_being_inserted]
FOR EACH ROW 
BEGIN 
    INSERT INTO `notification_queue` (`sent`) VALUES (0);
END$$
DELIMITER ;

From that point, all you need to do is make a crontab run on the server (say every minute) which selects from the notification table where sent = 0, send the notification and set sent = 1

As far as I know, that's the best way to get that information out of the DB without reading the bin logs.

If you need an example of the script to run with cron:

#!/bin/bash

DB_USER=''
DB_PASS=''
DB_NAME=''

ID=`mysql -u$DB_USER -p$DB_PASS $DB_NAME -Bse "SELECT notification_id FROM notification_queue WHERE sent=0 LIMIT 1;"`

if [[ ! -z $ID ]] 
then
    # SEND MAIL HERE
    RESULT=`mysql -u$DB_USER -p$DB_PASS $DB_NAME -Bse "UPDATE notification_queue SET sent=1 WHERE notification_id = $ID;"`
    echo "Sent"
fi