1.A trigger is a SQL code (similar with stored procedure) that is automatically executed by the Database Server when an UPDATE, INSERT or DELETE operation occurred in the database table that is associated with the table.
You can see details and example in the next article:
Triggers -- SQL Server[
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2.ASP.NET web application role is to generate the web pages that will be used by the user via a browser, so the web application should be focused in managing the user interface actions.
3.So you don't have to not mix these tho parts. The database triggers have to be created at the database level, then the triggers will be automatically generated in response to the database operation (INSERT, UPDATE or DELETE) over database table that have associated triggers no matter if the database operation will be generated in response to the user request that are coming from a web application or other type of application.
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