Active data based and triggers
Active data based and triggers Triggers are procedures that are automatically called by the DBMS in response to changes to the database and are specified by the database administrator (DBA). A database that has a set of triggers associated with it is usually called an active database. parts of the trigger A trigger description consists of the following three parts − · Event - An event is a change to the database that activates a trigger. · Conditional - The query is invoked as a condition and is executed when the trigger is activated. · Action - the procedure that is executed when the trigger is activated and its condition is true. Using triggers Triggers can be used for any of the following reasons − · Implement complex business rules that cannot be implemented due to constraints. · Triggers are used to test processes. For example, track changes to a spreadsheet. · Triggers are used to execute automatic actions when another affected action occurs. Trigger typ...