DB2 Triggers way to write query for your project

How to write Triggers? .

The following code shows the creation:

CREATE TRIGGER SALARY_UPDATE
BEFORE UPDATE OF SALARAY

ON EMP_TABLE
 FOR EACH ROW MODE DB2SQL
 WHEN (NEW.SALARY > (OLD.SALARY * 1.5))
 BEGIN AUTOMIC
 SIGNAL SQLSTATE '75001' ('RAISE EXCEEDS 50%');
 END

SALARY_UPDATE:  Trigger Name

The trigger will fire before actual update. It applies to all update rows. Begin and End are the actual Trigger statements. New value exceeds 50% of old salary. An error will raise. Triggers will be stored in Trigger package. Trigger packages also stored in SYSPACKAGE.