MySQL Events
A new feature of MySQL 5.1 is Events. Similar to a crontab or the 'Task Schedule', it allows you to execute an SQL statement at certain time intervals. The syntax is exceptionally easy to use:
CREATE EVENT [ IF NOT EXISTS ] event_name
ON SCHEDULE schedule
[ ON COMPLETION [ NOT ] PRESERVE ]
[ ENABLED | DISABLED ]
[ COMMENT 'comment' ]
DO sql_statement;
The first thought might be why you would want to run such a query from within MySQL. Running queries at regular intervals is sometimes necessary in large projects, e.g. for general cleanup etc. You can do this from within your chosen scripting language (PHP, Ruby etc), however, this creates another layer of dependancy. If your PHP script can't connect to the MySQL server, then it won't run - storing the event within MySQL overcomes this dependancy.
Continue Reading Add comment January 27th, 2006