|Triggers in Oracle are a special type of stored programs usually
maintained within a business algorithms/logical modules, watching
A data base trigger is basically a PL/SQL script, to be executed when the data in a table are modified. It resembles an event which is enforced by an internal security measure to avoid misappropriations that can surface during a business transaction.
|Usually triggers are invoked during DML ( DELETE, INSERT OR UPDATE
), some DDL ( CREATE, ALTER OR DROP), and Miscellaneous error from
the server ends.
|Advantages Of Using Triggers:
A database trigger can't call any stored procedure or function that contains COMIT, ROLLACK OR SAVEPOINT
|Types of Triggers : Depending upon, how and when a trigger is fired,
it may be classified as :
|Original Emp Table:
Below is an operation, on a copy of original table "emp".
Updating emp_copy1 table: