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Extended stored procedures [Table of Contents] Defaults and rules

Transact-SQL User's Guide

[-] Chapter 1 SQL Building Blocks
[-] Transact-SQL extensions
[-] Triggers

Triggers

A trigger is a stored procedure that instructs the system to take one or more actions when a specific change is attempted. By preventing incorrect, unauthorized, or inconsistent changes to data, triggers help maintain the integrity of a database.

Triggers can also protect referential integrity--enforcing rules about the relationships among data in different tables. Triggers go into effect when a user attempts to modify data with an insert, delete, or update command.

Triggers can nest to a depth of 16 levels, and can call local or remote stored procedures or other triggers.

Extended stored procedures [Table of Contents] Defaults and rules