SQL Triggers - An brief Introduction
Introduction Triggers can be defined as the database objects which perform some action for automatic execution whenever users try to do execute data modification commands (INSERT, DELETE and UPDATE) on the specified tables . Triggers are bound to specific tables. As per MSDN , triggers can be defined as the special kind of stored procedures. Before describing the types of triggers, we should first understand the Magic tables which are referenced in triggers and used for reuse. Magic Tables There are two tables Inserted and deleted in the SQL Server, which are popularly known as the Magic tables. These are not the physical tables but the SQL Server internal tables usually used with the triggers to retrieve the inserted, deleted or updated rows. These tables contain the information about inserted rows, deleted rows and the updated rows. This information can be summarized as follows: Action Inserted Deleted Insert Tab