What are TRIGGERS in SQL Server

 

TRIGGERS are stored program/ special stored procedure that execute automatically in response to database object, database, and server events.

For example, a trigger can be invoked when a row is deleted or inserted.

Types of Triggers:

1. DDL TRIGGERS: which fires/ triggers in response to CREATE, ALTER, and DROP statements. 
2. DML TRIGGERS: which are invoked automatically in response to INSERT, UPDATE, and DELETE commands.
3. LOGON TRIGGERS: Invokes only in responses to LOGON events.

SYNTAX:

CREATE TRIGGER:

CREATE TRIGGER [SCHEMANAME].TRIGGER_NAME ON TABLE_NAME AFTER {         [INSERT],            [UPDATE],            [DELETE]        } AS {        //YOUR CODE }

 

DROP TRIGGER

DROP TRIGGER [IF EXISTS] [SCHEMA_NAME].TRIGGER_NAME

DROP TRIGGER statement drops one or more triggers from the database.