Sherlock Group

Triggers are programmable events that react to queries and reside directly on the database server. Triggers can be executed before or after INSERT, UPDATE or DELETE statements.
with triggers, we can know what data has been insert, update or delete.
actually it’s easy to create, this is the example:

DELIMITER |

CREATE TRIGGER newsCounter AFTER INSERT ON News
FOR EACH ROW BEGIN
INSERT INTO NewsCount (newsItemCount) (SELECT count(*) FROM News);
END;

|
DELIMITER ;

that example, is to get and insert the news count at NewsCount table when user insert at News table and to get a triggers list at your database, you can run this:
SHOW TRIGGERS;

but u cannot create triggers from phpMyAdmin, it just can create from MySql Client like SQLyog (http://www.webyog.com/en/) and sometimes you have to be a super user to create triggers at your database. For more information bout triggers, u can visit this site: http://dev.mysql.com/doc/mysql/en/triggers.html

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