Example of After Insert Trigger in Oracle

Suppose we have table Employer which has following columns
Id , Name, Phone etc.

We can define insert trigger like that

CREATE OR REPLACE TRIGGER employerInsert
AFTER INSERT
|   ON Employer
   FOR EACH ROW  
DECLARE
   empName varchar2(10);  
BEGIN  
   -- Find username of person performing the INSERT into the table
   SELECT user INTO empName
   FROM dual;  
   -- Insert record into audit table
   INSERT INTO empHistory
   ( empId,
     Phone,
     username )
   VALUES
   ( :new.id,
     :new.phone,
     empName );    
END;