Lab 17.1 What Triggers Are

Lab Objectives

After this Lab, you will be able to:

✓ Understand What a Trigger Is

✓ Use BEFORE and AFTER Triggers

A database trigger is a named PL/SQL block stored in a database and executed implicitly when a triggering event occurs. An act of executing a trigger is referred to as firing a trigger. A triggering event is a DML (INSERT, UPDATE, or DELETE) statement executed against a database table. A trigger can fire before or after a triggering event. For example, if you have defined a trigger to fire before an INSERT statement on the STUDENT table, this trigger fires each time before you insert a row in the STUDENT table.

The general syntax for creating a trigger is as follows (the reserved words and phrases surrounded ...

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