The CREATE TRIGGER statement is used to define a trigger.
The CREATE TRIGGER statement associates it with changes occurring in a table.
It has the following syntax:
CREATE TRIGGER <name> <time> <event>
ON <table>
FOR EACH ROW
<body statements>
With the time and event, you must choose from an enumerated set of options:
CREATE TRIGGER [BEFORE | AFTER] [INSERT | UPDATE | DELETE]