You can create triggers for referential integrity individually or by default, and create your own triggers from the property sheet of a table (or view, if supported by your DBMS).
You can write a trigger from scratch directly in its property sheet, but we recommend that you use a trigger template and/or trigger template items to define the trigger code. These allow you to create triggers in a modular fashion, to make re-use of your trigger code easier and give your triggers more portability (see Trigger Templates (PDM)).