A Trigger is a procedure executed by the database server as soon as a DML statement is applied to a base table or a view table derived from it. Thus, the three trigger types INSERT, UPDATE, and DELETE are available; an UPDATE trigger call can be restricted to specific columns.
Relationships between a trigger and other objects:
1. Table Contains Trigger
2. Trigger Uses Module
1. A table can contain triggers; each trigger is assigned to exactly one table
(1-N[0]).
2. A trigger definition refers to exactly one module; a module can be used for defining a number of triggers (N[0]-1).
DOMAIN provides only informational functions for the defined triggers.
From the main menu, you can access any trigger list and then click on the 
toolbar button or select the Object / Design function to select the trigger and change to design
mode. In design mode, the trigger is displayed on a cardfile card with its parameters and constraints from the table definition.
As with all objects, you can define or query a comment for each trigger in the trigger list.