MSSQL Trigger Features and Types

October 5, 2024

A trigger, as the name suggests, is a stored procedure that is automatically executed when an event occurs on the database server.

MSSQL Trigger Features

There are many types of triggers, but in SQL SERVER, LOGON Trigger, DML Trigger, and DDL Trigger are mainly used.
LOGON Trigger creates a database session when a user logs in.
That is, Trigger can be used in response to the LOGON event that occurs when a database session is established.
DML Trigger can be used in response to an event when using the DML (Data Manipulation Language) language.
DDL Trigger can be used in response to various DDL (Data Definition Language) events that are mainly used.

MSSQL Trigger Features.

LOGON Trigger is executed in response to the LOGON event that occurs when a user’s session is established.
LOGON Trigger can be created and used in two ways.
The first way is to create it directly using Transact-SQL statements.
The second way is to create it as an assembly method in Microsoft. NET Framework CLR (Common Language Runtime) using a C# program and upload it to SQL Server for use.

DDL Trigger is a trigger that can be used in response to events for DDL operations such as CREATE, ALTER, DROP, etc.
For example, it is used when a log is required when modifying or deleting a table.

DML Trigger, mainly used by DBAs and developers, is a trigger that can be used in response to events for DML operations such as INSERT, UPDATE, and DELETE.
In other words, when the data in the table changes, the trigger event is automatically executed.
DML Trigger is often used to track data logs or apply data integrity.