Chapter 7, Problem 7.5RQ

Program Plan Intro

Trigger:

In a database, a trigger is a program joined to a particular table or view. It will executed by the DBMS (Database Management System), when certain events may occur using that table.

• It can be executed before or after the “SQL” commands which use the “INSERT”, “UPDATE” or “DELETE” operations or once for each modified row.
• If a trigger event has occurs, the trigger’s function will called at the time of handling the event.
• These events are handled using “BEFORE”, “AFTER” or “INSTEAD OF” trigger logics.