Oracle® PL/SQL® Interactive Workbook, Second Edition

Lab 17.2 Types of Triggers

Lab Objectives After this Lab, you will be able to: ✓ Use Row and Statement Triggers ✓ Use INSTEAD OF Triggers

In the previous lab of this chapter, you encountered the term row trigger. A row trigger is fired as many times as there are rows affected by the triggering statement. When the statement FOR EACH ROW is present in the CREATE TRIGGER clause, the trigger is a row trigger. Consider the following code:

▪ FOR EXAMPLE

CREATE OR REPLACE TRIGGER course_au 
AFTER UPDATE ON COURSE 
FOR EACH ROW 
… 

In this code fragment, the statement FOR EACH ROW is present in the CREATE TRIGGER clause. Therefore, this trigger is a row trigger. If an UPDATE statement causes 20 records in the COURSE table to be modified, this trigger ...