Pro T-SQL 2008 Programmer's Guide

Chapter 7. Triggers

SQL Server provides triggers as a means of executing T-SQL code in response to database object, database, and server events. SQL Server 2008 implements three types of triggers:classic T-SQL Data Manipulation Language (DML) triggers, which fire in response to insert, update, and delete events against tables; Data Definition Language (DDL) triggers, which fire in response to CREATE, ALTER, and DROP statements; and logon triggers, which fire in response to LOGON events. DDL triggers can also fire in response to some system SPs that perform DDL-like operations.

Triggers are a form of specialized SP, closely tied to your data and database objects. In the past, DML triggers were used to enforce various aspects of business logic, such ...